1. We might say that by virtue of the constitution of the mind, there are some principles of belief that are self-evident.⁹ If so, it does not matter whether God created our mental constitution, which could just as well have been produced by chance, determinism, or evolution. The point is that this constitution of the mind enables us to judge self-evident things. 2. Alternatively, because God created the mental constitution, the mind follows God's laws, which are never deceitful, as a common sense power to judge self-evident things.

⁶ Reid thinks that Descartes' excessive distrust of an "obscure something, which is supposed to be the subject or substratum of the [material] qualities" leads him to wrongly identify material substance as the essential attribute of extension (Reid, 2002a: 120-4).

⁷ James Harris had shown that the inquiry into the mind is more quickly stopped than the inquiry into material nature. Copenhaver stresses that the laws of nature have the same status in each realm: in both cases they are "contingently necessary" (Copenhaver, 2006: 455). See Bradford Bow's Introduction to this volume.

⁸ The medical use may be a paradigm of the intertwining theistic and philosophical connotations. For Reid, the contrivance of the body is a sign of our origin. Significantly, he refers to Galen to illustrate the first principle of necessary truths, that design and intelligence in the cause may be inferred with certainty from marks or signs in the effect (Reid, 2002a: 510).

⁹ Self-evident beliefs, for Reid, are expressed in propositions "which are no sooner understood than they are believed" (Reid, 2002a: 452).

Reid on Our Mental Constitution

Claire Etchegaray

In the introduction to the Inquiry into the Human Mind (1764), Reid defined "the anatomy of the mind" as the analysis that "finds out the simple and original principles of man's constitution, of which no account can be given but the will of our Maker" (Reid, 1997: 13-15). According to him, observation and introspective reflection on experience of mental operations offered the only way in which anatomists of the mind could identify general facts of perceptual belief.¹ He labelled them as "principles of common sense":

If there are certain principles, as I think there are, which the constitution of our nature leads us to believe, and which we are under a necessity to take for granted in the common concerns of life, without being able to give a reason for them; these are what we call the principles of common sense; and what is manifestly contrary to them, is what we call absurd. (Reid, 1997: 33;emphasis added) In the conclusion to the Inquiry, he introduced additional beliefs rooted in the natural constitution "called the common sense of mankind" (Reid, 1997: 215), which he later developed in the Essays on the Intellectual Powers (1785). Thus, Reid attributed the existence of self-evident beliefs to the virtue of our constitution. His treatment of the constitution in the anatomy of the mind, however, might be puzzling. Is the constitution of the mind hidden or observable? For Reid, it represents the nature by which mental operations are performed, and which can only be examined through these operations. In other words, it is known only in part-through its phenomena. This limitation introduces the question of why not restrict inquiries to the natural operations of the mind without mentioning this unknown constitution.² Reid's encounter with this ¹ See [START_REF] Wood | Hume, Reid and the Science of the Mind, in Hume and Hume's[END_REF][START_REF] Wood | Thomas Reid and the Culture of Science[END_REF][START_REF] Wood | Thomas Reid and the Common Sense School[END_REF][START_REF] Broadie | The Human Mind and Its Powers, in The Cambridge Companion to the Scottish Enlightenment[END_REF]. ² Hume seems to be more cautious in the introduction of the Treatise, by saying that "the essence of the mind being equally unknown to us with that of external bodies [ . . . ] any hypothesis, that problem was unexceptional with the terminology "by the original constitution" broadly used in the age of Enlightenment.

The phrase "original constitution" was closely connected to a form of nescience inspired by Newton's comments on the cause of gravitation in the "General Scholium" of the Principia mathematica and in Query 31 of the Opticks, which influenced different meanings in medicine and the science of mind.³ In experimental philosophy, anatomists of the mind repurposed the meaning of the term "constitution". John Locke, for example, argued we have no knowledge of the real constitution of things and experience provides only knowledge of nominal essences.⁴ In the Aberdonian tradition, George Turnbull held that an "inquiry into the facts and real constitutions" was possible by applying Baconian natural history and Newton's regulae philosophandi.He also believed that such an inquiry revealed the natural order created by God.⁵ David Fordyce argued in the preliminaries of the Elements of Moral Philosophy (1754) that "moral philosophy enquires, not how man might have been, but how he is constituted". Consequently, he claimed that "to determine the office, duty or destination of man [ . . . ] we must inspect his constitution" (Fordyce, 1990: 8).

Reid, who was a student of Turnbull, did not reveal any concerns about the objection that the "constitution" referred to some occult cause. Of qualities that were immediately perceived in matter but whose nature we ignore, such as secondary qualities, disorders we feel in our bodies and powers of bodies whether mechanical, chemical, medical, animal, or vegetable, he claimed that "[t]o call a thing occult, if we attend to the meaning of the word, is rather modestly to confess ignorance, than to cloke it" (Reid, 2002a: 216). Like in the science of nature, an anatomist of the mind can refer to a thing of which its constitution is pretends to discover the ultimate original qualities of human nature, ought at first to be rejected as presumptuous and chimerical" (Hume, 2000: 5). ³In medicine the "constitution" represented the contrivance of a healthy body or the nature of a part of the living body. The Latin 'constitutio' translates the Greek notion of kataskeue,asinthe titleofGalen'swork De optima corporis nostri constitutione.Thismedical sense is also the one to which Chambers exclusively refers in his Cyclopedia,apartfromthe political sense (Chambers, 1728: 312). On the debates aroused by the appeal to an original power (a power that the thing has "by its constitution") in physics, see [START_REF] Duchesneau | La physiologie des Lumières[END_REF][START_REF] Wright | Metaphysics and Physiology: Mind, Body and the Animal Economy in Eighteenth-Century Scotland[END_REF].

⁴ According to Locke, nominal essences "are made by the mind and not by nature" (Locke, 1975: 453). Yet "they are not made [ . . . ] arbitrarily" because the mind, in making its complex ideas of substances, "only follows nature". That is, the mind only joins particular ideas that are "supposed to have an union in nature" (455).

⁵ See his graduation thesis, De scientiae naturalis cum philosophia morali conjunctione (1723), and The Principles of Moral Philosophy (1740: 2).

unknown without imagining a refuge of ignorance.⁶ He cannot know its nature independently from its qualities but he can conceive this unknown nature. In particular, he identifies regular relations between things without being able to observe how their natures are connected. He only de facto observes that this is the case. These relations are general facts. Nonetheless, natural philosophy provides explanations, because these facts are necessary and are produced by a genuine power (a causal one), which cannot be exerted by inanimate or material agents.⁷ As in other Aberdonians' views, Reid's defence of experimental philosophy was grounded on theism with God as the first cause of all creation.⁸ From the belief that things were "the creatures of God", Reid argued, "they have a real essence, or constitution of nature, from which all their qualities flow; but this essence our faculties do not comprehend" (Reid, 2002a: 303).

The suspicion that this notion of the constitution disguises a refuge of ignorance reappears more seriously in Reid's philosophy of mind. Indeed, his analysis of mental faculties takes for granted the truth of the operation that it examines. The description of our mental operations implies that they enable us to know, according to him. For instance, perception should be studied as the ability to perceive reality itself. In this aim his reference to our constitution seems to account for his anti-scepticism along two diverging perspectives.

I. In What Way Does Knowledge Depend on Our Constitution?

In an unpublished and undated manuscript "Of constitution", Reid claimed that truth depends on "the constitution of the things" in general, and not on "our" constitution in particular. Only the discernment or perception of truth is relative to the knowing mind. Reid argued:

The truth of any proposition cannot depend upon the constitution; we except propositions in which the mind or some of its powers or operations is the subject of the proposition. But here we ought to distinguish between the truth of a proposition and my discernment of that truth. When truths are immediately assented to by all men as they are apprehended without instruction or reasoning, it may I think be said with PROPRI-ETY that the power by which we perceive the truth of the propositions is a part of our constitution. (Reid,n.d.: f.2) Although the first sentence is elliptic, the context makes clear that Reid means that the truth of any proposition does not depend on the constitution of the knowing mind. Truth depends on the constitution of the thing, which is expressed by some substantive representing the subject of a proposition. (That every adjective must belong to some substantive is a grammatical first principle. The ¹⁰ In addition to the epigraphs in the Inquiry and the Intellectual Powers, see the numerous hypostatic formulae (Reid, 1997: 174;2002a: 198, 205, 226, 575).

Both accounts represent plausible explanations of Reid's intended meaning that "common sense is purely the gift of Heaven" (Reid, 2002a: 433).¹⁰ In the first account, the acceptance of a perceptual belief requires no other reason than the perception itself. In this way, Reid's response to scepticism develops independently from his theistic convictions. The second account is an alternative explanation that credits theism as justification of natural beliefs. Both accounts, however, beg the question by referring to our mental constitution as an already truthful constitution of the knowing subject. This chapter sheds new light on Reid's reference to our mental constitution by distinguishing his approach from subjectivism, and then showing the way in which Reid treated the discernment of truth (and not truth itself) as a product of "our constitution". These important distinctions explain the proper sense in which the mind is a subject of knowledge in Reid's anatomy of the mind. (Reid,n.d.: 5) substantive denotes the subject of a proposition. This subject is not a self or an agent of knowledge. It is a thing.) Reid believed that everything "as it is made has a constitution [ ...] from which all its qualities, appearances, powers and operations do result" (Reid, n.d.: f.2). When the mind or an operation of the mind is the subject of a proposition, truth depends on the mental constitution, that is, the constitution of the substratum (or the support of observable qualities). But the discernment of that truth must be distinguished from the truth of the proposition.

Remarkably, in this context, the "subject" meant a support, not a self or an agent. Sir William Hamilton's later editorial interpretation of Reid's philoso-phy attempted to disentangle this old notion of subjectum as a knowing subject and a known object. Reid indeed wrote "the distinction between things in the mind and things external, is not meant to signify the place of the things we speak of, but their subject" (Reid, 1854b: 221b). Hamilton commented on the distinction between "things in the mind" and "things external" by saying that it covers the distinction between the thing that is id in quo and the thing that is id circa quod. In a statement typical of late modern thought, Hamilton identified the former as the subject, the latter as the object. He added that "in psychological language, the subject absolutely is the mind that knows or thinks-i.e. the mind considered as the subject of knowledge or thought; the object that which is known, or thought about" (ibid.). Starting from Hamil-ton's metaphysical distinction, the philosophical task is to understand how the subject can know the object. Certainly Reid's philosophy offered implicit answers to this question. But this formula inserts an opposition between the subject and the object that could be misleading to understand Reid'suseof "constitution" in the philosophy of the mind. At the end of this chapter, we shall recall this point in order to distinguish Reid's process from Descartes' and Kant's philosophies of mind.

When, at the beginning of the Inquiry, Reid wrote that Hume "leaves nothing in nature but ideas and impressions, without any subject on which they may be impressed" or that the sensation is related to "the mind, its subject" (Reid, 1997: 20, 40, my italics), he meant only that the mind is the thing in which the sensation exists. In the manuscript, Reid clarified:

In the case of the moral propositions, since the mind is their subject (in Reid's strict sense), their truth (not only our discernment) depends on the constitution of the human mind. But their truth does not depend on our discernment. Reid explicitly said: "the truth of the proposition as well our perception of that truth must be resolved into the constitution of the mind nor does this in my opinion open any door to scepticism" (Reid,n.d.,f.2). His reasons for stipulating that this did not "open any door to scepticism" require further examination.

A moral proposition could be understood in the restricted sense of an ethical proposition, or as a proposition about human nature more broadly. But in any case a moral truth is not subjective. At first sight, Reid targeted Hume. Nevertheless Paul Wood's chapter in this volume offers an alternative explanation.¹¹ In "Of constitution", perhaps Reid responded to critics claiming that his appeal to common sense as "apartofourconstitution" led to scepticism. Joseph Priestley's An Examination of Dr. Reid's Inquiry (1774) turned Reid's own argument against him. Priestley criticized that the "unknown something" called "common sense" reduces every judgment, either moral or factual, to feelings. If Priestley was correct in this criticism, Reid's references to the facts of our mental constitution resembled exactly what he ridiculed about Hume'ssystem.¹² Hume claimed in the Abstract of the Treatise that passion and belief are kinds of "natural instinct, derived from nothing but the original constitution of the human mind" (Hume, 2000: 408). In the second and the third books of the Treatise, he appealed to our natural constitution, first by referring to Francis Hutcheson but afterwards, step by step, by subverting the Hutchesonian account. Hume first wrote that "the most probable hypothesis which has been advan'dto explain the distinction betwixt vice and virtue, and the origin of moral rights and obligations, is, that from a primary constitution of nature certain characters and passions, by the very view and contemplation, produce pain, and others in like manner excite pleasure" (Hume, 2000: 194).¹³ He still appeared to agree with Hutcheson when he claimed there are "certain instincts originally implanted in our nature" and gave these examples: "benevolence and resentment, the love of life and kindness to children, or the general appetite to good and aversion to evil" ¹¹ See Chapter 8. ¹² This is a clue to the solution of James McCosh's puzzle: "the paper is the dimmest and yellowest of all: looks old. Query: when written?" (McCosh, 1875: 444). McCosh had suggested that the paper was an early manuscript (442). But it may have been written after 1774. I thank Paul Wood for drawing my attention to this point.

¹³ Here, this hypothesis appears clearly to be an alternative to the explanation by custom (Hume, 2000: 195). (Hume, 2000: 268).¹⁴ But he diverged from Hutcheson's philosophy at the beginning of the third book. "Take a wilful murder", Hume wrote. Where is the vice? There is a passion, there is a volition. Hume observed, "[h]ere is a matter of fact [but] 'tis the object of feeling, not of reason." He continued:

It lies in yourself, not in the object. So that when you pronounce any action or character to be vicious, you mean nothing, but that from the constitution of your nature you have a feeling or sentiment of blame from the contemplation of it. Vice and virtue, therefore, may be compar'd to sounds, colours, heat and cold, which, according to modern philosophy, are not qualities in objects, but perceptions in the mind. (Hume, 2000: 301;emphasis added) According to Hume, though there is a perception in the mind that we feel, there is no real moral quality that is perceived. The hypothesis of double existence (as he called it in the Fourth Part of the first Book) must be avoided, either in the case of secondary qualities or in the case of moral qualities.¹⁵ Reid disagreed with Hume. Reid maintained that the truth of the proposition "Ioughtto reverence my Maker" does not depend on a feeling or on a sensation (Reid,n.d.: 4). He extended this attack in the Intellectual Powers: "Icannothelp thinking, that a man who determined that there is more moral worth in cruelty, perfidy, and injustice, than in generosity, justice, prudence, and temperance, would judge wrong whatever his constitution was" (Reid, 2002a: 495, my italics). Reid'smeaningof "whatever his constitution was" represented a rejection of Hume's subjectivism. In this part of the Intellectual Powers, he examined first principles of necessary truths and this independence from our constitution might seem to be associated with his treatment of them. But, as we shall see, this independence is true of any truth. In his unpublished manuscript, Reid explicitly distinguished his thought from any subjectivism, either in morality or in the account of belief. He criticized Hume's theory of vivacity because it rendered the evidence dependent on our constitution. For Reid, truth may depend on the attributes that are conceived, or on the relations that the relative notion reveals. But it does not depend on our having conceptions, nor on our discernment.

¹⁴ Hutcheson had judged "probable, that the Pleasure is not the necessary Result of the Form it self, otherwise it would equally affect all Apprehensions in what Species soever; but depends upon a voluntary Constitution, adapted to preserve the Regularity of the Universe, and is probably not the Effect of Necessity but Choice in the Supreme Agent, who constituted our Senses" (Hutcheson, 2004: 80).

¹⁵ Moreover, unlike Hutcheson, Hume argued that vice is as natural as virtue, whatever is meant by "natural" (non-miraculous, habitual, non-artificial), and that selfishness is an original instinct (Hume, 2000: 304-5, 314, and 372).

An objection might be raised as to the dependence of the constitution in the case of knowledge of nominal essences and of secondary qualities. Knowledge or notions are considered relative insofar as they depend on the relationship between the constitutions of things, mind included. But they are not produced by the discernment of the mind. In the fourth essay of Intellectual Powers, "On Conception", Reid maintained that however imperfect (nominal or relative), it is true knowledge (Reid, 2002a: 303). For instance, Westminster Bridge is made of materials that are the work of God. But as the structure is the work of a man (an architect), he can have an adequate conception of it. Reid argued that "though I have never seen or heard of it before, if I am only made to conceive that it is a bridge from Westminster over the Thames, this conception, however imperfect is true" (ibid.). No one could have a conception of the internal constitution of the thing. Reid defended that "we must satisfy ourselves" with taking "attributes as facts" without deducing them from the real essence of things, but being convinced that "there is a subject to which those attributes belongs" (Reid, 2002a: 361-2). The only knowledge that we can have of bodies and minds is the knowledge of their attributes. Real essence is "above our comprehension". But the nominal essence is not a creature of our mind.

In the case of secondary qualities, Reid believed truth depends on the constitution of the things that are related. A secondary quality is the unknown cause of a sensation with which we are acquainted. "That smell in the rose is an unknown quality or modification which is the cause or occasion of a sensation which I know well," according to Reid. He believed "[t]he relation which this unknown quality bears to the sensationwithwhichnaturehathconnectedit, is all I learn from the sense of smelling" (Reid, 2002a: 202). Thence, the truth of a proposition assuming a perceived smell or colour does not depend on our discernment.

Besides, the reason for the contradistinction between contingent truths and necessary truths is not that contingent truths depend on our subjective constitution, and necessary truths do not depend on it. Actually, contingent truths are factual truths. Discerning them gives knowledge of existent things. Necessary truths are truths implied by the ideas or mere conceptions of things. Thus, logical and grammatical truths are necessary. Reid thought that moral and aesthetical truths were necessary truths too. In the passage quoted earlier, Reid wrote that the judgment on the moral worth of cruelty is held "whatever our constitution is". Actually, strictly speaking, neither factual truths nor necessary truths depend on our constitution-only the discernment of contingent and necessary truths depends on the narrowness of our powers as powers of created beings. Although already implicit in his Inquiry and the sixth essay of the Intellectual Powers, this distinction is more fully developed in his manuscript "Of constitution":

God has given us the faculty of judgment or common Sense. If we had not this faculty we could not perceive evidence even in first principles. I conceive this is all that is meant by those philosophers who say that they believe first principles, only because they are so constituted [ . . . ] But those philosophers in place of giving a reason for the belief of first principles, which it is impossible to do, give the cause of this belief, which is truly this that we are by our constitution endowed with the faculty of perceiving such first principles to be true. That is we have common sense. If a man asks me why I believe that twice two are equal to four? I conceive I cannot give him a more proper answer than this; I believe it is because I have common sense. But here I do not mean to assign common sense as an argument that perswades [sic] me of the truth of this axiom but as the faculty by which I discern its truth without any argument, & therefore my belief may be resolved into common sense as its cause, but not as a reason of my belief.

(Reid, n.d.: 9-10, emphasis added)¹⁶

Common sense, for Reid, was the "part of our constitution" through which we discern evidence. Common sense sometimes represented a power of judgment, sometimes a set of first principles of beliefs, and sometimes all our natural beliefs.

As shown in the introduction to this chapter, Reid entertained a two-sided meaning of "constitution": its non-phenomenal nature is unknown but its existence is discovered by observation. Thus, the power of judgment is only manifest in the mental operations of believing, which are considered natural insofar as they occur "by the virtue of" and as "a part of" our constitution. It remains to understand the connection between the study of our constitution and the identification of first principles.

In spite of the dualism by which Reid radically distinguished "the constitution of the material world" from the constitution of the human mind, he advocated the same method of inquiry in both cases:

We find one phenomenon to be the consequence of another, this of a third, and so on as far as we can go, & the farther the better; but we must stop some where and come at last to phenomena which cannot resolve into any other. And those ultimate phenomena which we cannot account for or resolve we call a part of the constitution of the system, or a law of nature. These laws of nature must be the operation of him that made the system, either immediate or by means of some subordinate causes which we have not discovered. Some ¹⁶ In the Inquiry, Reid wrote: "If there are certain principles, as I think there are, which the constitution of our nature leads us to believe, and which we are under a necessity to take for granted in the common concerns of life, without being able to give a reason for them; these are what we call the principles of common sense" (Reid, 1997: 33, emphasis added). In the Intellectual Powers,he claimed "such is the constitution of the human mind, that evidence discerned by us, forces a corresponding degree of assent" (Reid, 2002a: 481, emphasis added).

II. Why Does the Discernment of Truth Depend on Our Constitution?

According to Reid, descriptions of evidence in the philosophy of mind must treat evidence as truthful. Evidence represents a value, although in its description evidence is regarded as a fact.¹⁷ Reid explained:

We give the name of evidence to whatever is a ground of belief [ . . . ] What this evidence is, is more easily felt than described. Those who never reflected upon its nature, feel its influence in governing their belief. It is the business of the Logician to explain its nature and to distinguish its various kinds and degrees. (Reid, 2002a: 228-9) The difficulty of evidence "more easily felt than described", for Reid, involves not reducing it to a bare feeling. Otherwise, logicians run the risk of being charged with subjectivism and scepticism. In the Intellectual Powers, Reid recalled that "first principles, or intuitive judgments" must be distinguished from judgments "which may be ascribed to the power of reasoning". The former are expressed by propositions that are "no sooner understood than they are believed", in contrast to the latter, which are inferred from another proposition (Reid, 2002a: 452-3). This presents the problem: does tracing discernment to the fact that this power of ¹⁷ On the 'linking-up between questions of fact and questions of value', see [START_REF] Rysiew | Reid and Epistemic Naturalism[END_REF][START_REF] Rysiew | Pragmatism and Reid's "Third Way[END_REF] part therefore of the constitution of the system is always the last result of our physical enquiries when we proceed analytically [sic]; and to be assumed as a first principle when we would explain the phenomena of nature synthetically. (Reid,n.d.: 1) A law of nature or a part of the constitution was an ultimate phenomenon which must be accounted for as an original fact. It was a nescient result of an inquiry into the causes which, being regressive, was analytical and which stops for negative reasons when an investigation could not proceed and further. But it could be considered as a first principle from a synthetic point of view, when it satisfactorily "explains" the subordinate phenomenon. Indeed, laws of nature were operations of the maker and in the case of the natural constitution,efficacy was the operation of the transcendent Creator. Another inquirer may later discern the details of such an explanation by discovering how this original fact occurs (Reid, 1997: 15). We have now to examine why, in the philosophy of mind, the first principles of common sense were principles of evidence, which are eventually termed "principles of truth". judgment is part of our constitution beg the question? Undoubtedly, Reid, in a way, presupposed the truthfulness of our faculties. The objective of this section is to define his intentions in making such a presupposition. The literature focuses on addressing what allowed Reid to think that our natural beliefs are justified or are true knowledge. This issue involves two further questions: why did Reid claim that the first principles of truth were intuitive and was he justified in dismissing scepticism as irrelevant? Contributions to this subject often underline pragmatist arguments that involve an implicit acknowledgement of evidence as evidence. This consideration, however, mainly concerns the justification of our beliefs.¹⁸ But Reid sought an explanation for our true beliefs. This explanation necessarily entails a justificatory ingredient, since it must explain the fact that they are justified or warranted. Reid did not simply claim that knowledge was a natural or a divine gift. His inquiry into our constitution showed how natural powers operate and how they give us access to reality. In doing so, he applied a method depicted in the manuscript "Of constitution", which demonstrated that his approach could not be reduced to the mysterious appeal to common sense condemned by Priestley.

According to Reid, the task of logic was not to find reasons for self-evidence. On the contrary, logic described every kind of evidence (e.g. perception, memory, deductive inference, probable induction, etc.). Note that a reason for a belief is only one of several kinds of evidence, namely an inferential one. The logical accounting for evidence seems to introduce a reason for it when it says that the ability to discern evidence is part of our constitution, which is the work of God. In order to avoid Hume's mistake, Reid argued that our beliefs must be treated as bare effects of the operations of our mind, and we must not reduce evidence to a psychological effect without any normative value. But Reid clearly indicated that the self-evidence of perception, remembrance, induction, and so on, was not conveyed by such a reason. Reid wrote: Shall we say, then, that this belief is the inspiration of the Almighty? I think this may be said in a good sense; for I take it to be the immediate effect of our constitution, which is the work of the Almighty. But if inspiration be understood to imply a persuasion of its coming from God, our belief of the objects of sense is not inspiration; for a man would believe his senses though he had no notion of a Deity. He who is persuaded that he is the workmanship of God, and that it is a part of his constitution to believe his senses, may think that a good reason to confirm his belief. But he had the belief before he could give this or any other reason for it. (Reid, 2002a: 231-2) Reid distinguished between natural belief, which assents to evidence but does not need to believe in God to do so, and philosophical confirmation of belief,an acknowledgement that natural belief is a "part of our constitution" (common sense) as "the workmanship of God". The veracity of God is a reason from which the conclusion that our natural faculties were truthful is drawn. But we do not need this philosophical justification to discern perceptual, memorial, and other kinds of evidence.¹⁹ Focusing on the justification for our natural beliefs, therefore, did not fully explain Reid's intentions. We have to determine the explanatory function of the inquiry into our constitution. The hypothesis that will be developed in this chapter is the following one: to say that our beliefs are about real things according to the laws of our nature is to attribute this to the exertion of powers instituted by a Transcendent Being. This belief assists understanding facts that are observed when we reflect on evidence, because perceptual belief transcends sensation, inductive belief transcends past experience, and testimonial belief transcends words heard.

The first principles, for Reid, represent laws of nature that must explain conceiving an attribute or a relation that does not depend on our having conception, and that we believe in an existence that does not depend on our discernment. They do so because explaining instinctive belief as self-evident is tantamount to describing the operation of transcendence. On suggestion at the beginning of the Inquiry, Reid wrote:

Why sensation should compel our belief of the present existence of the thing, memory a belief of its past existence, and imagination no belief at all, I believe no philosopher can give a shadow of reason, but that such is the nature of these operations: they are simple and original, and therefore inexplicable acts of the mind. (Reid, 1997: 28) The ultimate fact, for Reid, involves acknowledging that a sensation is necessarily taken as a sign of the thing, which is conceived as existent in the perception. Analytically, we cannot say more. But synthetically, the law of suggestion explains every thing that needs to be explained: (1) why we perceive one thing (the extra-mental thing) and why the perception does not have two objects (one in my mind and an extra-mental one); (2) why the belief in its existence is not concluded from another reason. This is explained only by the fact that there is a metaphysical gap between sensation and perception that is transcended by a power given in our constitution. Rebecca Copenhaver and Keith De Rose stress that there is an "external relation" between the sensation and the object of perception, or in Reid's words, there is "no connection that arises necessarily ¹⁹ See [START_REF] Poore | Theism, Coherence, and Justification in Thomas Reid's Epistemology[END_REF] from the nature of the things", especially no similitude.²⁰ As we cannot have a perception without having any sensation, there is, however, a connection, which is attested by the regularities of experience. But it does not stem from the nature of the things. Even in the case of the perception of secondary qualities, although the way we describe the object of perception (the extra-mental thing) depends on the sensation, there is no similitude, as we have seen, between the nature of the secondary quality and the nature of the sensation. The laws of our constitution can explain the fact that we are in the presence of the thing only if they are the way in which transcendence, as it were, operates within us.

Transcendence is still at work in other beliefs about reality, testimonial and inductive beliefs included. It is at work, in fact, when we naturally interpret any thing as a sign. In addition to sensation, indeed, there are two other kinds of natural signs: natural language (gesture) and natural causes (Reid, 1997: 58-61).²¹ In the latter case, by virtue of repeated observations, we simultaneously discover that some thing is a sign and learn its interpretation through experience. Then, another first principle describes the "external relation" between past experience and future expectation: the inductive principle. Although Reid agreed with Hume's observation that there is no reason by which the expectation is inferred from past experience, he opposed Hume's position on the fact of nature involved in our probable belief. Reid, in contrast, tried to account for inductive evidence as genuine grounds for belief and can only do so by appealing to "the constitution of human nature" that "ties together [ ...] those things which were in their nature unconnected" (Reid, 1997: 50). In the case of natural language, without any induction, we know that a specific facial expression signifies a particular emotion. In an analogy between perceptive evidence and testimonial evidence Reid showed that testimonial belief was a belief about the same things signified by the speaker's discourse, and not only about the speaker's belief. The object of belief is the thing itself and not any mental object in the speaker's mind or in the hearer's mind (nor inferred through this mental object). Artificial signs are not only linguistic signs, but signs of reality by virtue of our constitution. To account for testimonial belief, the naturalist must describe transcendence.

Although Reid does not employ the term "transcendence" in this context, phenomenology currently allows us to use it in the philosophy of mind. Moreover, the term occurred in the nineteenth-century reception of Reid's writings, [START_REF] Copenhaver | A Realism for Reid: Mediated but Direct[END_REF]. See also De Rose, 1989[START_REF] Buras | The Function of Sensations in Reid[END_REF]. For a different approach, perhaps overlooking the metaphysical gap, see [START_REF] Pappas | Sensation and Perception in Reid[END_REF] ²¹ Sensation suggests a thing of which we had never before any notion or conception (Reid, 1997: 59), although facial expression and signs of natural language suggest some things notions of which are given by nature (Reid, 1997: 51).

which proves relevant for two reasons.²² First, it appropriately denotes the typical gap (i.e. the absence of necessary connection) that is observed in any exertion of true power. Reid argued that "[p]ower in the proper sense is under the command of him who has the power, and we cannot infer the act from the power because there is no necessary connection between them" (Reid, 2003: 21-2, my emphasis). This gap occurs both in the philosophy of mind and in the philosophy of nature. The power exerted in perception is as transcendent as the power exerted in gravitation. Notwithstanding, when applied to the typical gap observed in our mental operations, the term is relevant for another reason. In perception, induction, and testimonial belief, the gap is not only observed (as it was in the science of nature), it is crossed. It would appear odd to call the gap between a so-called cause and a so-called effect observed in external nature ('so-called' because signs of each other) "transcendent". Notwithstanding, in the philosophy of mind, the experience of perception (and induction, testimony) proves to be experience of self-transcendence. Close examination of this mental operation shows that there is no reason why we conceive a thing and believe that it exists when we have a particular sensation. And yet we do conceive and believe in this external existence. Referring to our constitution as 'God's workmanship', the anatomist of the mind is in a position to account for this mental gap-crossing without overlooking the gap. In Reid's version of common sense philosophy, a first principle provides an explanation. It is a law of nature that describes some induced regularities, produced by an agency. Reid's methodology in "Of constitution" suggests that, in the philosophy of mind, first principles are mental facts. Nonetheless in the Intellectual Powers, Reid's enunciation of the first principles of contingent truths is ambiguous. For instance, the first does not consist in holding that every affirmation of the existence of every thing of which I am conscious is true. Reid rather claims: "I hold as a first principle the existence of every thing of which I am conscious." In the published work, the existence of the thing is the alleged first principle. Although my aim is not to deny this ambiguity, the examination of what the first principles have to account for (namely evidence as such) helps to explain why Reid made the enunciation of the first principles in such forms. Since Reid treated the first principles as laws of nature, which must explain our discernment of truth as such, he concluded they were first principles ²² In a note in an abridged edition of Reid's Essays on the Intellectual Powers of Man, James Walker quotes a lecture given by the French translator of Reid's works, Theodore Jouffroy: "From the results of observation, and solely by the application to these results of a conception of reason, the mind arrives at a consequence that transcends them" (Reid, 1854a: 444).

III. Conclusion

By claiming that Reid's theism "helps the reliabilism", Philip De Bary hints that it "gives an explanation for the reliability of the faculties" (De Bary, 2002: 187-8). If we are right, indeed, Reid's reference to God explains their reliability because it makes sense of the observation made by the philosopher when he sees that they cross the gap. Reid's belief that our faculties were part of God's creation makes intelligible the self-transcendence described in Section II. It did not, however, imply that Reid intended to demonstrate their truthfulness or to refute the sceptic by proving first that our constitution is not delusive. Indeed, Reid's answer to the ²³ Undoubtedly, there is a shift. Another ambiguity is often pointed out in the literature: are the first principles propositions, objects or beliefs taken for granted? On this point, see [START_REF] Van Cleve | Reid on the First Principles of Contingent Truths[END_REF][START_REF] Wolterstorff | Reid on Common Sense[END_REF] ²⁴ Letter to Lord Kames, 16 December 1780 in Reid, 2002b: 145. of truth. The first principle was the fact that we discern the truth of the existence of every thing of which we are conscious as truth. This explains why, for Reid, the first principle was the existence of this thing.²³

In the case of material phenomena, agency is external to any material thing. The philosophy of material nature would not perform any explanatory function if there were no agent transcendent to matter, and there is no evidence that active principles can be inherent to matter.²⁴ Now, in the case of mental phenomena, a first principle provides an explanation of our perception of evidence. Remarkably, there is no need to learn by induction that there is a law of nature in mental phenomena to follow it. By feeling a sensation of hardness we instinctively know the cohesion of the parts of the thing we are touching. We do not need to know that divine agency is at work. Reid believed divine agency was involved in our mental operation. The explanatory function of the philosophy of mind is only performed if the philosopher, who proceeds first analytically and then synthetically, becomes aware that this transcendent agency is at work. Here, agency is not incompatible with the nature of the subject since this subject is not material-it is the mind as such. The mind is not the agent of the mental operation but the thing in which there is an activity consisting in transcending the nature of our feeling, sensation, hearing, and so on. Now we can address the suspicion that the appeal to our mental constitution is a refuge of ignorance in Reid's philosophy of mind, especially the fear that Reid's reply to the sceptic begs the question by presupposing that the mind is a knowing subject.

²⁶ See Etchegaray, 2013: 142-5. sceptic did not consist in saying that because they are God's creation, our faculties are reliable, but rather in using "the means which Nature has furnished" in order to bring controversies about first principles to an issue: the unprejudiced use of judgment, the sense of ridicule, and some "track-record arguments" (Reid, 2002a: 461-7).²⁵ These means aimed at awakening the sense of evidence by prompting the exercise of common sense, not at demonstrating that the sceptic was wrong by inferring the reliability of our faculties from our non-delusive constitution.²⁶ In particular Reid did not think that the reliability must be concluded from a demonstrative reason, as, for instance, from the divine origin of our constitution. He believed that if led to reflect on his own mental experience, the sceptic would confess that he always implicitly acknowledges evidence as a just ground of belief. Reid admitted that it would be impossible to demonstrate that our constitution was suited to discerning evidence. In the manuscript "Of constitution",he conceded that our constitution might appear contingent for two reasons: (1) either the Maker of this constitution might "have given us one part of it without an other, for instance the power of perceiving mathematical or physical truths without the power of perceiving moral truths", or (2) he might "have given a contrary constitution so as that what we now perceive to be true either in morality or in other things, should by means of that other constitution be perceived to be false" (Reid, n.d.: 3). These possibilities were not incongruent with God's omnipotence. Regarding the role of sensation, Reid considered that we cannot conceive a perceived object without it. Perhaps God could have made us in another way. This offered an explanation for why he wrote that it was a "cause or occasion". "Occasion" referred to a fact without which perception does not occur given our actual constitution, but which could have been absent in another created nature. Moreover, logic did not require a demonstration to rule out the possibility that God was a great deceiver. Having no reason to think that our constitution was fallacious, Reid sought to describe our cognitive powers by reference to the transcendence at work in it. Refusing the burden of proof, and finding no reason for suspicion, Reid developed a realistic philosophy of mind. We have shown why experimental theism provided him with adequate means to achieve this objective. References to God are very expedient to assist the ²⁵"Conceiving that the testimony of our senses, and of all our faculties, excepting that of consciousness, ought not to be taken for granted, but to be proved by argument" was Descartes' mistake according to Reid. "Other men, from the beginning of the world, had taken for granted, as a first principle, the truth and reality of what they perceive by their senses, and from thence inferred the existence of a Supreme Author and Maker of the world" (Reid, 2002a: 515). Reid's criticism of Descartes' circle is widely stressed from [START_REF] Alston | Thomas Reid on Epistemic Principles[END_REF][START_REF] Poore | Theism, Coherence, and Justification in Thomas Reid's Epistemology[END_REF] philosopher for the description of evidence, and such assistance is useless to convince the sceptic.

In this approach, is the mind a knowing subject?²⁷ Section I has shown that the proper method for the philosophy of mind must avoid subjectivism. The mind is termed 'a subject' in the sense of a SUBJECTUM to which discernment is inherent. Nevertheless, at the beginning of the Essay on the Intellectual Powers, Reid introduced the following "principle taken for granted [ . . . that the] very operation we are conscious of supposes an agent that operates, which we call mind" (Reid, 2002a: 42). In doing so, we conceive our mind as ours only through common sense. On the second of the first principles, Reid argued "that the thoughts of which I am conscious, are the thoughts of a being which I call myself, my mind, my person" and again, on the sixth that "we have some degree of power over our actions" and consequently that we are "agents" (Reid, 2002a: 472). Certainly, we may believe that we have some degree of power over our mental acts. In other passages, Reid suggested that this power is mainly a power of attention (Reid, 2002a: 64). Thus, the mind can function to some degree as an agent-at least we have a natural belief that it can play such a role. For instance, we believe (we know, strictly speaking, according to Reid) that we could perceive better. But the laws of our mental constitution remain the creature of another agent, its Creator.²⁸ Our agency is exerted only in the use of law-governed intellectual powers.²⁹ In Reid's work, the notion of subject in the sense of self, agent, and person occurred through a belief that stems from the transcendent efficacy of our nature. This modern concept of subject is not a philosophical requisite to answering the sceptic, nor to describing our mental operations.

For this reason, the Reidian response to scepticism departed from a Cartesian order and did not presuppose the mind as a transcendental subject of knowledge. A 'Cartesian order' is the name that Reid would willingly apply to the following: first I know that I exist as a self, and then and only then, I have to prove that the other objects of my ideas are existent too, thanks to God's veracity.³⁰ Reid's logic and response to the sceptic involved a naturalistic method (a method examining the nature of things, mind included) that required an appeal to God'sefficacy ²⁷ On the role and significance of Reid's concepts in the emergence of the modern subject, see De [START_REF] De Libera | When Did the Modern Subject Emerge?[END_REF][START_REF] De Libera | La double revolution[END_REF] ²⁸ On the distinction between operation and action, activity and agency of the mind, see Jaffro, 2014.

²⁹ Strictly speaking, an active power is not law-governed. ³⁰ Although this interpretation of Descartes' Meditations is questionable, it is Reid's own. Actually Descartes does not proceed so in the Meditations. But this is the way Reid introduces it (2002a: 115-16).

As every truth expresses some attribute of a thing, or some relation between two or more things, the truth depends on the nature of the thing whose attribute is expressed. The truth of this proposition that a lion is a ravenous beast, depends upon the constitution of a lion, and upon nothing else. The truth of this proposition, that the sun is greater than the moon, depends upon the magnitude of the sun and the moon, and upon nothing else.

¹⁸ See[START_REF] Rysiew | Reid and Epistemic Naturalism[END_REF][START_REF] Rysiew | Pragmatism and Reid's "Third Way[END_REF][START_REF] Jaffro | La rétorsion du sens commun et la possibilité du scepticisme, in Comment peut-on être sceptique?[END_REF][START_REF] Poore | Theism, Coherence, and Justification in Thomas Reid's Epistemology[END_REF]


Laurent Zimmer
email: laurent.zimmer@ecp.fr

Tapish Agarwal

Laser-induced ignition and plasma spectroscopy in a turbulent liquid fueled combustor

Laser induced ignition was applied in a turbulent two staged aeronautical combustion chamber. It was coupled to extensive on-line spectroscopic measurements to determine the local equivalence ration within each spark. This value was found correlated to the probability of ignition and it was shown that establishment of the complete flame in the combustor required not only the creation of an initial kernel but also favorable flow patterns. Criteria for ignition based on experimental results are proposed in a particular combustor but the techniques and subsequent analysis developed may be applied to other injection devices.

Introduction

For high altitude relight or aircraft engines, laser ignition may be an alternative to actual spark plug as it offers the possibility to create the initial kernel directly in the inner recirculation zone. This not only minimizes the ignition delays but also increases the probability of ignition due to absence of quenching at the wall and more favorable fluid flow conditions. However, the fate of a single shot is usually considered as being stochastic, mainly because it depends on many parameters. Many previous experiments dealing with laser ignition considered mainly statistical analysis ([1-2]) but it may be interesting to better understand the actual ignition process to have some deep insights of single events taken with a relatively large number of diagnostics. This approach would ease the development of models and may be more easily compared to numerical simulations, for which converging probability analysis is still a challenge.

Experimental devices

In the present case, a staged liquid fueled injector is used [START_REF] Providakis | Characterization of the Acoustic Interactions in a Two-Stage Multi-Injection Combustor Fed With Liquid Fuel[END_REF]. The fuel is injected through a central pressurized atomizer while air is swirled. Dodecane is introduced at an overall equivalence ratio of 0.7 with only air being pre-heated at 473K. A schematic view of both injection device and optical diagnostics is provided in Figure 1. Two different swirlers are used in co-rotating arrangement. Two quartz walls are used to allow a good optical access and several diagnostics are used simultaneously to provide conditionally based analyses. To actually measure the equivalence ratio as well as the deposition of energy and initial kernel size, a two-dimensional Laser Induced Plasma Spectroscopy technique (2D-LIPS) has been recently developed [START_REF] Agarwal | Two dimensional Laser Induced Plasma Spectroscopy for the measurements of local composition in gaseous flow and sprays[END_REF]. This requires the use of two ICCD equipped with interferential filters centered on specific atomic transition (hydrogen and oxygen). Without a precise calibration in presence of droplets, this technique only provides the atomic H/O ratio, which is monotonically linked to mixture fraction. Two high repetition rate lasers (10kHz) are synchronized with a fast camera (Photron, 20kHz) to actually image the droplets of the spray in a plane of the chamber. This allows also applying statistical analysis, such as correlation tools to estimate the displacement of droplets within two laser pulses. Laser induced ignition was achieved by focusing the second harmonic of a Nd:YAG through a lens of focal 100 mm. The position of the laser and the lens could be changed with respect to the chamber so as to investigate different points.

Results and discussions

Several experiments were performed in order to first investigate statistical properties of the laser-induced ignition. Some points had a very high probability of ignition (in the recirculation zone) whereas those located mainly in the outer recirculation zone of the spray had little success. It was decided to specifically concentrate on points with relatively low probability to sort out success and failures based on actual time resolved measurements. Among the main results, the actual H/O atomic ratio (representing the equivalence ratio), the size of the initial kernel are obtained by 2D-LIPS. To take into account the dynamics of the flow, dedicated post-processing tools have been used to estimate the actual growth/decay of the aerodynamic structure (PVC : precessing vortex core) based on planar measurements of Mie scattering by droplets. Seven ignition events were analyzed versus 12 failed cases. Overall results are displayed in Figure 2 with both local H/O ratio versus initial kernel and varying strength of the PVC. It can be seen that many igniting cases had a higher kernel size for a similar H/O as compared to failed attempts. This is explained by the existence of a critical kernel to overcome heat losses by convection. Among the eight sparks that had a good H/O together with an initial kernel above the critical size, the only case that failed corresponded to a case for which the PVC tended loose energy. PVC is considered as being an important feature for ignition in the inner recirculation zone as offering a region of lower pressure, hence easing the convection of an initial kernel towards the injector.

Fig. 1 .

 1 Fig. 1. Schematic view of the injector and the different optical diagnostics used.

Fig. 2 .

 2 Fig. 2. Actual mean H/O ratio versus initial kernel size (left) and decay of the strength of the precessing vortex core 10ms before spark as compared to 30ms.

Conclusions

Combined measurements of H/O, kernel size and aerodynamic structures could explain most of ignition attempts. This strategy opens new experimental investigations based on the detailed characterization of single events rather than based on statistical analysis only. This may ease comparisons with numerical simulations for which statistically converged data remains out of reach.


Introduction

With the end of the Cold War the international security environment changed fundamentally. The removal of the superpower conflict saw an initial wave of hope and cuts in military spending, but it quickly became clear that the world was still a dangerous place, and war and conflict remained endemic in many parts of the world. Conflicts had changed; in general they were intra rather than interstate, and there was a resurgence of interest in the role of economic forces in civil wars. In fact the discipline of economics has always included the study of conflict and war. At first its theories were global, focusing upon the role of inter-state war in economic development and then later became more focussed, offering partial analyses of conflicts. This partly reflected the changing nature of international relations over time, as modern nations were formed in an environment of international conflict. But it also reflected a change in the nature of the dominant paradigm, a move from political economy to neoclassical economics.

Early mercantilist theories explained war as predation, allowing enrichment and ensuring the supply of raw materials by conquest and imperialism. Later, in the 19th century after the Napoleonic Wars, the development of trade was characterized by relatively peaceful international relations; and a liberal perspective, which saw war as a fetter on the development of trade, had more influence. The growth of industrialisation created social conflicts that became the focus of economists' research, particularly Marx who gave little time to the study of international issues. But when the survival of capitalism was threatened by competing systems (notably Communism), the volume of economic studies focussing on issues of militarism and conflict increased enormously. This was true of Marxists, but also Institutionalist and Keynesian economists, who in some cases integrated war into their general perspective on the functioning of the capitalist system.

The development of nuclear weapons radically changed the international order, with a new balance of power (the balance of terror) and the limitation of international conflicts to peripheral zones. New economic analyses of conflict have then been developed to explain these changes, favoured by the progress in economic techniques. These studies were much focused on strategic concerns, economic issues taking only second place. Therefore, the economic discourse on conflict became depoliticized, except for a few heterodox works, in particular Marxist ones.

Today economic analysis has to deal with a renewal of economic problems in current conflicts, whether internal or international. The supply of raw materials, internal inequalities generating new demands, changes in the world economic hierarchy, development of asymmetrical conflicts… To deal with these new aspects of international relations, current economic theory presents partial and very sophisticated analyzes, in contrast to the global character of former economic theories. Furthermore, liberal orthodoxy dominates most studies devoted to defence economics. This has not decreased the importance of the issues or the debate, but it has moved them from the arena of economics into the more general arena of the social sciences, particularly international relations, politics, international political economy and development studies.

This paper provides a brief overview of how the understanding of conflict and war has changed over the years. Section I looks at the global perspectives that developed from liberal, mercantilist and Marxist schools of thought. Section II then examines the less general analysis of international conflict, in the form of arms races and the development of the theory of civil conflicts. Finally, Section III draws some conclusions

I -Global analyses of military conflict

The history of economic thought reveals three main economic explanations of international conflicts: one, that they are the result of State failure; two, that they are the result of the quest for power and wealth; and, three, that they are a result of the nature of capitalism. There are, however, few works in economics that have been entirely devoted to the war and peace issues.

I.1. Conflicts as State failure: the liberal creed [START_REF] Kant | Toward Perpetual Peace: A Philosophical Sketch[END_REF] argued that the progress of civilization tended to bring peace at the global level. He described wars as morally reprehensible, but also as a way to reach an ideal state of civilization, a world federation characterized by a universal and lasting peace. [START_REF] Fukuyama | The end of history and the last man[END_REF] provides a recent example of this belief, arguing that the political changes of the late 1980's and the spread of democracy and liberalism, meant that war would become less and less probable. Many 'liberal' economists were also ready to announce the end of international conflicts thanks to the spread of civilization and, in particular, the spreading of free market economies. To them the costs of war are clear, namely the destruction of resources, the interruption of trade and the burden of debt when war is financed by loans. Thus, wars are considered to be counterproductive and cannot be justified by the benefits of predation and territorial expansion, since the surest way to increase the national economic growth is through the development of trade with prosperous neighbours. This leads to a denial the legitimacy of wars, which are seen as resulting from a perversion of the political process, with the State undertaking military actions to serve particular interests. This analysis was already developed in the work of Adam [START_REF] Smith | The Wealth of Nations[END_REF], where the State is a place of conflicts and the decision to make war, or peace, depended on political processes, on the balance of power between the different social classes. The merchant class was seen as responsible for involving the country in useless colonial conquests and other military conflicts that were beneficial to them as a group. The founder of the British Classical School was inspired by the utilitarianism of Locke, according to whom universal peace was part of a law of nature. Man is naturally social and so war results from imperfections in human nature, in particular of ambition, and as such it can be only a temporary phenomenon. This theory directly inspired the liberal economic theories, which see the economy as governed by an "invisible hand", a natural order in which the State should not intervene [START_REF] Coulomb | Adam Smith: A Defence Economist[END_REF].

Other economic analyzes of militarism and wars are even more hard-hitting. Pareto (1897) violently criticized the rise in military expenditure of his time, denouncing it as a regressive government policy that was leading to growing state economic control. For Pareto wars were of no economic use for contemporary civilized societies and could only be explained as resulting from the megalomania of leaders and the use by governments of external threats to ensure social cohesion and to cover up corruption in executive circles1 . He also denounced military expenditures because they led to tax increases. This concern with vested interests continued, with the term "military industrial complex" being used by US President Eisenhower in 1961, to warn against the potential threats of the coalition of interests between defence industries, military and all those who benefited from increased military spending and, as a result, conflicts. This was taken up by J.K. [START_REF] Galbraith | The culture of contentment[END_REF] to explain why the rise of the American military budget was not subject to democratic control. The existence of an external threat and the continuation of international conflicts reinforced the military sector's power and guaranteed the perpetuation of advantageous contracts for many companies, engineers, scientists, academics and other researchers. This type of analysis has been used beyond the liberal perspective, most notably in the contemporary Marxist analysis of militarism [START_REF] Dunne | The Political Economy of Military Expenditure: An Introduction[END_REF].

I.2. Conflicts necessary for power: the mercantilist perspective

During the 17 th century, while the Physiocrat theory defended the concept of a "natural order" in the economic sphere, political theory developed in the opposite direction. In the Leviathan, Hobbes (1651) presented international relations as anarchic, with a nation's survival depending on its management of a permanent state of war. Peace was then the absence of war and as such perceived in a negative way, as an artificial temporary state. Such ideas have influenced the "realist" school of thought in international relations and politics and some economics have also echoed these ideas. Prior to capitalism, the dominant mercantilist perspective considered the nation state as needing to produce wealth in the form of gold and this required running trade surpluses -encouraging exports and discouraging imports in a world in which trade volumes were considered fixed. This was one of the first instances of significant government intervention in the economy and it encouraged wars in Europe and imperialism beyond, as the powers fought over available markets. It meant that creating wealth required military strength which in turn required economic strength. In such a system economic openness would need hegemony to provide the collective goods of security and stability.

In the 19 th century, the Historical School (notably as developed in Germany and the UK) saw the maintenance of strong national defence as an important component of economic prosperity and rejected the idea of disarmament. Wars and military values were considered useful for the government, as they developed the population's will to participate in the reinforcement of the national power. Thus strong interventionist policies were needed to promote national economic development. F. List (1841) went even further in emphasising the importance of economic patriotism and justifying wars as reinforcing national power on the world scene.

More recently a 'neo mercantilist' perspective has linked the realist and mercantilist theories, seeing countries and states as being motivated primarily by the desire for military and economic power, rather than ideals or ethics. War is seen as an irreducible human trait in earlier works but a curable one in more modern ones, and conflict is inevitable unless there is some dominant hegemonic force -Pax Britannica, or more recently the US.

I.3. Militarism and the survival of the capitalist system

Another economic approach to conflict is based on a global explanation of the functioning of capitalism, as evidenced by the Institutionalist and Marxist approaches. Indeed, [START_REF] Schumpeter | Capitalism, socialism and democracy[END_REF] argued that capitalism would probably disappear because of middle-class disinterest in foreign policy and of the lack of charismatic political leaders able to gain national adhesion, while [START_REF] Veblen | Imperial Germany and the industrial revolution[END_REF] distinguished various types of capitalism, the Anglo-Saxon one being more peaceful than the Dynastic one. This distinction was used in the 1980's to explain Japanese and German commercial success as due to the specific nature of their societies, which were argued to be more prone to economic patriotism.

The Marxist approach saw international conflict as a consequence of class war. In the capitalist mode of production, internal contradictions related to overproduction and the resulting fall in the profit rate are temporarily solved by exports and imperialism. Some Russian pre-revolution theories, such as [START_REF] Lenin | Imperialism, the highest stage of capitalism[END_REF], predicted an increase in military conflicts between capitalist countries at the stage of imperialism, because of their competing ambitions on the world market. This did not occur, however, and later Marxist analyses focussed on explaining capitalism's post World War II survival and prosperity by its high level of militarism, which as wasteful expenditure provided a solution to endemic overproduction [START_REF] Howard | A History of Marxian Economics[END_REF]. Military Keynesianism also presented military expenditure as a way to solve the economic crisis, but in this case it was just like other public expenditures [START_REF] Smith | Military Expenditure and Capitalism[END_REF].

II. Economic models of conflict

Advances in econometrics and modelling since the second world war have been applied to the economic study of strategic issues, such as arms race, international alliances, or the economic consequences of military expenditure. The growing sophistication of the mathematical and statistical techniques has opened the way to many improvements on the basic models. [START_REF] Intriligator | Research on Conflict Theory[END_REF] listed 64 possible combinations between the 8 existing types of possible analytical approaches (differential equations, decision theory, control theory, game theory, bargaining theory, uncertainty and stability theory, action-reaction models, and organization theory) and 8 subjects of studies. This list is much larger today, as mathematical techniques applied to economics have become even more numerous and sophisticated, for example the application of chaos theory. This section considers how the economic analyses of international conflicts and civil conflicts have developed.

II.1. Economic analysis of international conflicts

In the 1960's, arms race models became a popular way to explain governmental strategic decisions in the field of defence. The founding model from [START_REF] Richardson | Arms and insecurity -A mathematical study of the causes and origins of war[END_REF] was based on three equations representing political, strategic and economic factors. The model accounts for the armaments of two rival countries through an action-reaction process, with capability, m1 and m2, related at time t by the equations:

Where ai are exogenous 'grievance' terms, bi are 'reaction' terms, whereby each country responds to the military capability of the other, and ci are 'fatigue' terms, usually representing some internal limitations on a country's military spending/capability. Interestingly, this approach was not welcomed by the US government in the Cold War environment as it implied that arms races had no 'good' and 'bad' guy but were simply the result of one reacting to the other.

During the US-Soviet arms race, numerous arms race models were developed and improved to simulate the strategic interactions between the superpowers [START_REF] Brito | Arms races and proliferation[END_REF]. These included the explicit modelling of rational economic decision-making, different dynamic specifications, game theory approaches, and empirically with the use of approaches such as co-integration. The search for clear empirical evidence of 'arms races' has, however, met with rather limited success, with even the apparently obvious example of the Cold War superpower arms race proving ambiguous and very much dependent on model specification2 . Certainly, these models were more strategic than economic, as they did not integrate the economic characteristics of the countries. And yet, the political collapse of the Soviet Union and the end of the cold war was at least partly due to the burden of military expenditure on the Soviet block during the cold war's revival in the 1980's.

Since the end off the cold war the popularity of arms races has waned. Their focus on strategic comparable competition between two powers, had seemed less relevant as asymmetric conflicts between countries with high technology weapons and those without became much more likely. Several examples, like African conflicts or the attacks of September 11, show that technological superiority does not guarantee safety nor victory in the event of war. Asymmetric arms race models have to specify not only the protagonists and their strategic objective but also their cost constraint and the internal decision-making process [START_REF] Dunne | Managing Asymmetric Conflict[END_REF].

Recent work has considered arms races, but in a more general perspective. [START_REF] Dunne | The Political Economy of Military Expenditure: An Introduction[END_REF]Perlo-Freeman (2003a and2003b) and [START_REF] Collier | Greed and grievance in civil wars[END_REF], sought to generalise the concept of an arms race by looking at the demand for military expenditure across a large group of countries, using either cross-section or panel data, incorporating a range of economic, political and security variables, and including variables for the aggregate military expenditure of neighbours and rivals. These models have typically shown that a country's military expenditure is significantly and positively influenced by that of those around them3 . Dunne and Perlo-Freeman (2003b) break this down, finding that the significant positive influence comes through the military spending of 'Potential Enemies'. They suggest that this indicates, if not an arms race as such, then at least arms race-like effects, or spillover effects, where there is some tendency towards an action-reaction pattern of military spending between hostile nations [START_REF] Murdoch | Civil Wars and Economic Growth: Spatial Dispersion[END_REF][START_REF] Dunne | The Econometrics of Arms Races[END_REF].

Beside arms race models, another economic theory of conflicts has been developed during the 1990's, the Conflict Success Function (CSF). In these models, the inputs are the investments in fighting efforts of the two sides and the outputs are their relative degree of success in the conflict: either the probability of winning or the share of the pie that goes to each side4 . While there is a vast military literature on success in battle, there is relatively little econometric work on conflict success functions5 . One problem with this type of analysis is that it either treats aggregate military strength as a single aggregate, or distinguishes only between labour and capital, members of the armed forces and their equipment. In fact determining the optimal force structure involves four main choices for both labour and capital. The first choice is the number of varieties of types of forces: army, navy, air force, each made up of specialised types of soldiers, sailors and airmen, each with distinct roles and associated equipment. There is some substitution between these; a target may be destroyed by a tank shell, a bomb dropped from an aircraft or a cruise missile launched from a submarine. The second choice is the quality of those forces, determined by R&D for equipment and training for labour. The third choice is the quantity of each. The final choice is whether they are obtained domestically or from abroad. This choice is primarily important for equipment, where security of supply for spares in case of conflict is often important, but does also occur for labour for those countries that use foreign soldiers [START_REF] Dunne | Managing Asymmetric Conflict[END_REF].

More generally, economic models such as CSF are in the tradition of ultra-liberal economists (Gary Becker), which associate all human activities, including criminal ones, with an economic calculation. The relevance of such cost-benefit analyses can be questioned, however, particularly when the conflict is atypical, as it is in the case of terrorism. Indeed, rationality has limited value in explaining terrorism, as for example it is difficult to see what the economic rationality of suicide attacks is, particularly to the individual bomber. There have in fact been relatively few economic analyses of terrorism, with the work of Todd Sandler the best known. In [START_REF] Enders | Patterns off transnational terrorism, 1970-1999: alternative time-series estimates[END_REF] a model is developed to highlight cycles of transnational terrorism (with periods of weak activity alternating with periods of strong activity) to deduce some recommendations for the political authorities at various periods of the cycle. But such conclusions may appear less than straightforward, given the sophistication of statistical method used.

II.2. The theory of civil conflicts

While the end of the Cold War, with its proxy wars and superpower involvement in local conflicts, may have reduced the intensity of conflict, it certainly did not reduce the Security Web by averaging the military burdens of those countries in the web, finding it to have a significant positive effect on a country's military burden. number. Civil or intra state wars became prevalent and the 'new' wars were considered by [START_REF] Kaldor | New and Old Wars: Organised Violence in a Global Era[END_REF] to be very different to the 'old' and only understandable within the context of political, economic and military globalisation. Although local, the wars tended to have a transnational connection, often through diaspora, and there was a blurred distinction between war and organised crime. There were few real military battles, with skirmishes more likely, and a tendency for militias to target civilians. New war economies were seemingly based upon plunder and black-marketeering, sometimes supported by aid, and sustained through continued violence. This was not helped by the tendency of the 'international community' to work with the protagonists to broker peace deals rather than the civil society that existed outside of the conflict [START_REF] Kaldor | New and Old Wars: Organised Violence in a Global Era[END_REF]. A harder look at the endemic and continuing conflicts in Africa was particularly challenging, and it started to become clear that the continuing struggles needed some source of income, that this was often natural resources and that it was possible that the resources' control had become the object of the struggle overtaking any previous goals. It was not a breakdown of the system but a way of creating a new system of income and profit and power [START_REF] Cramer | Civil War is not a Stupid Thing[END_REF].

While these new characteristics of conflicts were being taken on board by areas in social science other than economics, often using realist state-centred theory, economists have generally ignored them. Instead economists developed models which formalized the liberal idea, based on methodological individualism, that public action results from the balance of power between various interest groups. Non-cooperative game theory was then used to build explanatory models of governmental decisions, which when combined with macroeconomic factors, provided a better understanding of internal factors determining the State propensity to conflict or militarism. Thus, economic analyzes developed during the 1990's rejected ethnic rivalry as the main explanation of civil wars, and emphasised the role of the economic and of internal political determinants. One of the pioneer contributions was [START_REF] Grossman | A General Equilibrium Model of Insurrections[END_REF], who presents the choice of the level of military expenditure by a government as determined by the probability of an insurrection. This study gave rise to many analyzes of internal political conflicts likely to lead to civil wars, using Conflict Success Functions [START_REF] Skarpedas | Cooperation, Conflict, and Power in the Absence of Property Rights[END_REF]Hirschleifer 1995). These analyzes have since been subject to many improvements, in particular aiming at showing that the nature of the political regime and of its economic policy can influence the outbreak and the nature of an insurrection [START_REF] Azam | Capacité d'engagement de l'Etat, redistribution et croissance[END_REF].

Whereas Hirschleifer (2000) assimilates rebellion and search for profit (greed), implying that the only motivation of rebels is their personal enrichment, [START_REF] Collier | Greed and grievance in civil wars[END_REF] have more recently moved to a more nuanced approach that sees civil wars as arising from a complex arbitration between greed and grievance. Denying the importance of the ethnic factor in civil wars, Collier underlines the role of economic and institutional determinants. His models and econometric applications aim at explaining the various actors' rationality and the outbreak of civil wars. Africa especially is studied. In Collier's theory, any rebel movement needs to have a business activity to ensure sufficient resources to go into war and these resources come from the exploitation and sale of raw materials. Thereafter, the rebels' motivation for ending a conflict may be diminished by the fact that the war economy works well for them and provides a good living. According to Collier, this situation explains the importance in the number of civil wars in the poorest countries and the existence of "conflict traps" [START_REF] Collier | The Bottom Billion[END_REF]).

Collier's works have been much criticized, notably on technical issues: problems of data sample, of periodic divisions, etc. But a more fundamental criticism of this approach is that under the guise of being apolitical it inevitably presents rebel groups in a negative way. It means believing that any government, however corrupt, must be maintained in power rather than allowing a civil war to start. With this approach, the worst predation which can be exerted on the population is that rising from the military burden; the legal predation (notably by the tax system) by a corrupted government is preferable to a state of civil war. Collier's analysis shows the difficulty that social scientists face in remaining objective. Although economic rationality does not explain all conflicts, by reinstating the economic dimension in the analysis of civil wars, Collier's theory contributes to a better understanding of these phenomena6 .

III Conclusion: The triumph of liberal neoconservatism?

Although as this paper has shown, economics has always included the study of conflict and war, it has tended to remain a diversion from the discipline's main focus. Nevertheless, an impressive literature has been developed that has influenced research in other subject areas, such as international relations and political science. The early theories were global, focusing upon the role of inter state war in economic development, but more recently they have become much more focussed and have reached an unprecedented level of technical sophistication. While this has led to important insights, it is still possible to question whether significant progress has been made in improving our understanding of conflicts, international or civil. The models are somewhat partial and abstract and one really needs to ask whether the modelling of Conflict Success Function provides a means of understanding international conflict, even if economic factors are central. It certainly begs a number of important questions, such as how the fact that a State's bellicosity may be motivated by a will to reinforce its internal control or to support the military industrial complex contrary to the general interest, may be introduced, or how the influence of long-term political changes at world level, such as described by political analysts, for example with the "power transition" theory, may be taken into account.

Certainly the analyses of conflict that use microeconomic methods remain partial, when compared with global explanations developed in the 19th and 20th centuries by the Marxist, Institutional, Keynesian, or even Classical economists. The rise of scientificity in social sciences fundamentally altered the analysis of conflict, and the search for a rationalization of the causes and consequences of war led to an apparent depoliticisation of economics discourse. Yet these theories are not politically neutral. The theory of the "diffusion of the democracy" is an example of imposition of neoconservative dogmas under scientific cover of neutrality. It is the theory of democratic peace with globalisation added to it, suggesting a role for multi layered governance structures to deal with weak states with anti-capitalist and anti-liberal attitudes which were reinforcing their backwardness in a globalising world. But more recently this has been replaced by the US hegemony pursuing democracy within states and protecting democracy from external aggression.

This new orthodoxy brings together neoclassical analysis of conflict and the general neoliberal perspective of the new realists in international relations. This sees war as a result of pre or anti-capitalist sentiments and groups, sees the solution to conflict as a global neo-liberal system and accepts that military action might be needed in the shorter run to create the right conditions (dealing with rogue states and terrorists). As a result the need to maintain the basis to produce the means of destruction through high military spending can be justified as can the hegemonic role of the US. Such a world view is certainly not what was expected at the end of the Cold War and is certainly not uncontested 7 . It represents a limited view of the world that is being brought into question with the continuing problems in Iraq and Afghanistan. The challenge for economics is to develop an alternative to the new orthodoxy that will support initiatives that strive for peace and security, a challenge that has been taken up by the creation of Economists for Peace and Security 8 .

University Pierre Mendès France, Grenoble, France

University of the West of England, UK

In fact such ideas were not new. In the 16th century, Machiavelli presented militarism as a remedy for civil war or internal disputes.

India and Pakistan provides one of the few examples where researchers have been able to provide consistent evidence of a Richardsonian arms race. But even here, Oren (1994) has offered an alternative approach, based on hostility levels between the two countries, under which the apparent arms race disappears. Numerous attempts have been made to estimate arms races for Turkey and Greece, using a variety of theoretical and econometric models, without clear evidence of an arms race emerging. (E.g.Dunne, Nikolaidou and Smith (2003))

Dunne and Perlo-Freeman (2003a) develop an attempt by[START_REF] Rosh | Third World Militarisation: Security Webs and the States they Ensnare[END_REF] to deal with general strategic effects by using the concept of a security web, instead of dyadic relationships between neighbours and other countries (such as regional powers). Rosh calculates the degree of militarisation of a nation's

There are two main functional forms used in which success depends either on the ratio of the forces or the difference of the forces. Hirschleifer (2000) provides a discussion of CSF, with many military and nonmilitary examples, which captures the spirit of the literature.

 5 An exception is[START_REF] Rotte | On the Production of Victory: Empirical Determinants of Battlefield Success in Modern War[END_REF], who use a data set

of 625 battles 1600-1973 to estimate an equation to explain victory by the attacker in battle: a zero to one dependent variable.

It is also interesting that it provides an instance where neoclassical rather than Marxist economics introduces a materialist interpretation of a phenomena..

Economics, conflict and war

Fanny Coulomb 1 and J. Paul Dunne 2