What is a natural kind? As we shall see, the concept of a natural kind has a long history. Many of the interesting doctrines can be detected in Aristotle, were revived by Locke and Leibniz, and have again become fashionable in recent years. Equally there has been agreement about certain paradigm examples: the kinds oak, stickleback and gold are natural kinds, and the kinds table, nation and banknote are not. Sadly agreement does not extend much further. It is impossible to (...) discover a single consistent doctrine in the literature, and different discussions focus on different doctrines without writers or readers being aware of the fact. In this paper I shall attempt to find a defensible distinction between natural and non-natural kinds. (shrink)

‘… and he arranged it all. It's done me the world of good, I can tell you. And that's why I said that yesterday was both yesterday and two years ago.’‘Well, it still sounds nonsense to me. I told you H. G. Wells would do you no good.’.

Aristotle's account of akrasia is unsatisfactory for a number of reasons. First, his account of the problem is coloured by a number of unattractive assumptions and preoccupations; second, his central claim, that akrasia involves a temporary displacement of knowledge, deals at best with only a small number of cases; third, he is wrong to suppose that the akrates is typically someone overwhelmed by passion. We need to follow Davidson in recognising that the central problem consists in a failure to convert (...) intention into action. Any solution must involve a recognition that we are dealing with a range of very different kinds of case, which demand different kinds of treatment. For example sometimes agents are overtaken by passion; sometimes they coolly and calmly do the wrong thing; sometimes they are insincere; sometimes they are suffering from a weakness of will; sometimes they are guilty of some kind of self deception; and sometimes they may have difficulty in comparing the goods and evils available. (shrink)