Those who say philosophy is the search for truth overlook that other pursuit of philosophy, the search for nonsense. They miss a good part of the fun. The investigation of really magnificent confusions or of irresistibly compelling conceptual illusions usually has it all over plodding along after wherever the argument leads. Chapters 4 and 5 risk that kind of dullness. They pursue some good reasons for not believing Hume's first premiss. But the present chapter considers the bad, but seductive, reasons so many have had for accepting that premiss. This is important. It is usually not enough to give good arguments against a prevailing prejudice. One must also explain why so many have found it compelling.

Something close to Hume's first premiss (strong version) is held, or just assumed, by a great many contemporary philosophers. We can find something like it, for example, in D. Davidson's classic article ‘Actions, Reasons and Causes’ (1963). (This and other contemporary versions are discussed in Chapter 4.) Davidson presents as relatively unproblematic what I will call his ‘pro-attitude account’ of what it is for an agent to have done something for a reason (or to have a reason for doing it). Where an agent ‘does something for a reason’ (or ‘has a reason for doing something’):

1. 1. He has some sort of pro-attitude toward actions of that kind,

and

1. 2. He believes that his action is of that kind,

where ‘pro-attitude’ covers not only:

1. a. Desires, wantings, urges, promptings,

but also:

1. b. Moral views, aesthetic principles, economic prejudices, social conventions, public and private goals and values.