¹ The first, though not necessarily the second. For, if there is a time-lag between the plant's lacking x and this taking effect, it will for this period need x but not ail.

² This might be thought to produce a difficulty for conceiving of the relations between the two cycles along the lines I have suggested. For where the plant never had x, it did not have x even before its ailing in r was initiated. How then can its lack of x be said to have initiated its ailing in r? But in changing circumstances a lack not previously operative can become operative. A man may lose his job because of lack of education though he was just as uneducated when he held it.

³ I have been led to take this objection seriously by Mr Mendel Kramer.

⁴ The account I shall consider has some resemblance to, though it is in no way modelled upon, the analysis of desire given in Russell, Bertrand, The Analysis of Mind (London, 1921)Google Scholar chap. iii. Russell's analysis has been criticised in Kenny, Anthony, Action, Emotion, and Will (London, 1963)Google Scholar and Pears, David, ‘Russell's Theory of Desire’ to be published in Russell in Review (Toronto, 1974).Google Scholar

⁵ Cf. Armstrong, David, A Materialist Theory of the Mind (London, 1968) chaps 5 and 6.Google Scholar

⁶ See e.g. Chomsky, Noam, ‘A Review of B. F. Skinner's Verbal Behaviour’ reprinted in The Structure of Language, ed. Fodor, Jerry A. and Katz, Jerrold J. (Englefield Cliffs, N.J., 1963)Google Scholar, and Taylor, Charles, The Explanation of Behaviour (London, 1964) passim.Google Scholar

⁷ The man who needs water might not believe that he needs it. He might simply desire it, or to have it, and be aware of this. I am not here concerned with such a case. Hidé Ishiguro has pointed out to me the need for making this distinction, though she has argued — and here I would not agree with her — that the man who believes that he needs water is in much the same situation as the man who believes that he needs vitamins.

⁸ Throughout this discussion of need I have not discussed what might loosely be called ‘hypothetical’ needs, e.g. the burglar's need for a jemmy, the dictator's need for a brutal police force.

⁹ These issues are discussed, though in varying terminology, in, e.g., Benn, S. I. and Peters, R. S., Social Principles and the Democratic State (London, 1959)Google Scholar; Barry, Brian, Political Argument (London, 1965)Google Scholar; Marcuse, Herbert, Five Lectures (Boston, 1970)Google Scholar; Runciman, W. G., Relative Deprivation and Social Justice (London, 1972)Google Scholar; Rawls, John, A Theory of Justice (London, 1972)Google Scholar; Illich, Ivan, Tools for Conviviality (London, 1973)Google Scholar; Feinberg, Joel, Social Philosophy (Englefield Cliffs, N.J., 1973).Google Scholar

¹⁰ If by any chance it is not already clear, I have not thought of the confusions and misrepresentations I have been talking about, nor (more generally) of internal strategy, as restricted to conscious mental activity.