1. This point is well stated by Jaegwon Kim, ‘On the Psycho-Physical Identity Theory’, American Philosophical Quarterly 3 (1966), 227–235.
2. For work along these lines, see my ‘Actions, Reasons and Causes’, The Journal of Philosophy 60 (1963), 685–700; The Logical Form of Action Sentences’, in The Logic of Decision and Action (ed. by N. Rescher), Pittsburgh, 1967; my comments on Richard Martin in Fact and Experience (ed. by J. Margolis), Oxford, 1969; `Causal Relations’, The Journal of Philosophy 64 (1967), 691–703.
3. The difficulty discussed here is raised by Anthony Kenny in Action, Emotion and Will, London, 1964, 2nd ed., chap. VII. In the second and third papers mentioned in the previous reference I devote more space to these matters and to the solution about to be outlined.
4. Georg Henrik von Wright, Norm and Action, London, 1963, p. 23.
5. ‘Facts and Propositions’, reprinted in The Foundations of Mathematics, New York, 1950, pp. 140, 141.