Richard Holton

Traditional interpretations of legal doctrine have seen the actus reus and the mens rea as independent elements of a crime. Here it is argued that various puzzles surrounding the nature of intent and of attempt can be better addressed if we reject that idea. Following Williamson’s account of knowledge, it is suggested that the two are inseparable. The crime consists in the performance of an intentional act. It follows that an act has been performed and that the performer is in a certain mental state. But these cannot in general exist independently of each other.

In this paper, we contend that the psychology of addiction is similar to the psychology of ordinary, non-addictive temptation in important respects, and explore the ways in which these parallels can illuminate both addiction and ordinary action. The incentive salience account of addiction proposed by Robinson and Berridge (1993; 2001; 2008) entails that addictive desires are not in their nature different from many of the desires had by non-addicts; what is different is rather the way that addictive desires are acquired, which in turn affects their strength. We examine these “incentive salience” desires, both in addicts and non-addicts, contrasting them with more cognitive desires. On this account, the self-control challenge faced by addicted agents is not different in kind from that faced by non-addicted agents – though the two may, of course, differ greatly in degree of difficulty. We explore a general model of self-control for both the addict and the non-addict, stressing that self-control may be employed at three different stages, and examining the ways in which it might be strengthened. This helps elucidate a general model of intentional action.

We aim to find a middle path between disease models of addiction, and those that treat addictive choices as choices like any other. We develop an account of the disease element by focussing on the idea that dopamine works primarily to lay down dispositional intrinsic desires. Addictive substances artifically boost the dopamine signal, and thereby lay down intrinsic desires for the substances that persist through withdrawal, and in the face of beliefs that they are worthless. The result is cravings that are largely outside the control of the addict. But this does not mean that addicts are bound to act on such cravings, since they typically retain their faculty of self-control. The issue is one of difficulty not impossibility. Controlling an addictive craving is exceedingly demanding.