The Possibility of a Welfare Policy in a World of Emotion-Driven Individuals: A Humean Point of View

Based on Hume's major philosophical works and on some of his Essays, this paper discusses formally the feasibility, from a Humean point of view, of a welfare policy which would aim at promoting the highest individual happiness whereas individual decisions, like individual happiness, are determined not only by allocations of goods, but also by an emotional state. It is shown that both the intertemporal structure of the problem and the role that Hume granted to the ‘calm passion' allow solving the problem, at least in principle.Hume;happiness;decision;pleasure;belief;emotion;violence of the passion;welfare policy

Metal, Money and the Prince - John Buridan and Nicholas Oresme after Thomas Aquinas

The monetary theories that stem from the works of Thomas Aquinas on the one hand, John Buridan and Nicholas Oresme on the other hand, share common roots: they appear as the result of careful commentaries upon Aristotle's moral and political works. Nonetheless, they differ on both the understanding of money as a measure of values, and on the conditions that allow the emergence of money from a stock of metals which could be, like natural wealth, allocated to different uses. Therefore, they illustrate respectively a “conventional” and a “metalist” theory of money. The question raised by Buridan's and Oresme's political representations is to make them consistent with monetary theories elaborated separately. In this respect, they supplied a composite picture in which the Prince is an essential character. Acting as the efficient cause of money, he is expected to achieve the adjustments required by the real changes affecting money. But the question of the debasements of money gave rise to different lines of answers. While Buridan concluded with an identification of the Prince and the common good, Oresme drew a Prince whose power is partly controlled through adequate institutions and incentives, partly limited by the consequences of his policy choices.Oresme; Buridan; Thomas Aquinas; Thomas d'Aquin; money; monnaie; conventional theory of money; théorie métalliste de la monnaie; metalist theory of money; théorie conventionnelle de la monnaie

The Valuation of Decision and Individual Welfare: A Humean Approach

Drawing on passages in Book II of the Treatise of Human Nature (1739-40), in the Enquiry Concerning the Principles of Morals (1751), in the Dissertation on the Passions (1757), and in some of the Essays (1777), this paper is built upon Hume's distinction between three alternative valuations of an individual position: desire (which leads to action), interest, and happiness. The difficulty comes from the fact that desire does not depend on pleasure as an impression, but on the force of an idea of pleasure, based upon a belief in the realisation of the correlative impression. Typically, this belief is linked to the underlying emotional state, expressed in the degree of violence of the passions, which governs both the individual's reactivity to pleasure, and his preference for present (compared to future) pleasures. On the contrary, interest and happiness do not depend on the distortion introduced by beliefs, and are directly linked to pleasure. It is shown that the decisional valuation only coincides with interest in the case of what Hume called a “calm passion”, which gives birth to the greatest happiness.Hume; decision; welfare; desire; pleasure; belief; passion; intertemporal choice; utility; interest; happiness; décision; bien-être; plaisir; croyance; choix intertemporel; utilité; intérêt, bonheur

Norm, Virtue and Information: Individual Behaviour and the Just Price in Thomas Aquinas' Summa theologica

This paper aims at putting forward the analytical stake of the few passages that Thomas Aquinas devotes to prices and exchange, mainly in the Summa Theologiae. At first sight, his objective is to enlighten a confessor vis-à-vis his penitent, or the judge in an ecclesiastical tribunal, by way of a group of normative prescriptions, tending to distinguish that which is just in commercial transactions from what is not. But on second thoughts, this objective leads the author to a more complex construction, which involves establishing a referential norm - the just price - to which the transaction price should be compared. It is recalled here that resorting to the just price - the discussion of which chiefly takes place in the commentaries on the Ethics avoids any consideration of individual behaviour. However, this last comes to the forefront when the issue dealt with is to explain the reasons why such a transaction price is equal to, or on the contrary departs from the just price. Thomas Aquinas' treatment of this issue allows one to acknowledge a) that individual behaviour is characterized by virtue or by vice in various informational contexts, and b) that the making of a transaction price is the result of a negotiation process between buyer and seller. In a context of correct information, where the partners are both virtuous, Thomas Aquinas explains why the transaction price is equal to the just price - in the exchange in se - or could differ from it - in the exchange per accidens. But focussing on the exchange in se, both an asymetry of information and the vice of at least one of the partners give rise to deception strategies leading to transaction prices, presented as just by the party who knows it is not, and agreed upon as just by the deceived party. Lastly, the possibility of retaining information during the negotiation process paves the way for the opportunity for the virtuous seller to protect himself against the higher power of negotiation of a possible vicious partner. Although aiming at a different goal, Thomas Aquinas thus provides a complete theory, not only of the just price, but more generally of exchange, in which ethical considerations become decisive in determining transaction prices.Just price; juste prix; medieval economics; pensée économique médiévale; Thomas Aquinas; Thomas d'Aquin; ethics; éthique

Riemann Zeroes and Phase Transitions via the Spectral Operator on Fractal Strings

The spectral operator was introduced by M. L. Lapidus and M. van Frankenhuijsen [La-vF3] in their reinterpretation of the earlier work of M. L. Lapidus and H. Maier [LaMa2] on inverse spectral problems and the Riemann hypothesis. In essence, it is a map that sends the geometry of a fractal string onto its spectrum. In this survey paper, we present the rigorous functional analytic framework given by the authors in [HerLa1] and within which to study the spectral operator. Furthermore, we also give a necessary and sufficient condition for the invertibility of the spectral operator (in the critical strip) and therefore obtain a new spectral and operator-theoretic reformulation of the Riemann hypothesis. More specifically, we show that the spectral operator is invertible (or equivalently, that zero does not belong to its spectrum) if and only if the Riemann zeta function zeta(s) does not have any zeroes on the vertical line Re(s)=c. Hence, it is not invertible in the mid-fractal case when c=1/2, and it is invertible everywhere else (i.e., for all c in(0,1) with c not equal to 1/2) if and only if the Riemann hypothesis is true. We also show the existence of four types of (mathematical) phase transitions occurring for the spectral operator at the critical fractal dimension c=1/2 and c=1 concerning the shape of the spectrum, its boundedness, its invertibility as well as its quasi-invertibility