Introduction

I have been presenting a behaviourist account of the mind that takes off from the claim discussed in Chapter 5 that a rational agent is disposed to behave in a way that is sensitive to practical rationality. In Chapter 6 I argued that practical rationality is open-ended and dynamic. This means that at any one time, in being sensitive to practical rationality, an agent's behaviour is governed by a particular version of practical rationality, but that this version, as part of its very nature, is subject to revision.

Given this notion of what it is to be a rational agent the behaviourist claim at the very beginning of the book may be amplified a bit. The original claim was this:

The amplified version is this:

To describe the particular version of rationality that someone's way of behaving is governed by at any one time is to describe the person's mind at that time. In this chapter I spell out that claim with respect to beliefs, and in the next with respect to intentions.

In the next section I introduce Richard Braithwaite's account of belief developed in the 1930s. The core of his theory is that believing a proposition is being disposed to act as if that proposition were true.