As such, logical behaviourism lends itself to a basically materialist view of mind and body. This is mainly because behaviourism is commonly applied as a reductionist theory. This means that statements that are generally seen as implying mind-body dualism are reduced, or translated, into talk about physical events. So, when we say, “I will be delighted if Tottenham win the Premiership”, what I am really saying is that if they do win the league, you will find me dancing round the streets singing, “Spurs forever!” (or something like that). On the other hand, if I make no observable reaction, you may doubt that I am a Spurs’ supporter at all.

From this viewpoint, beliefs are explained as “dispositions”. For instance, although it may not be an observable fact that I know the answer to a certain question – such as “What is the capital of France” – it will surely a thing that may be tested. On the other hand, if I cannot show that I know the answer, then I cannot be said to know it. So, in this way, talk of “dispositions” may account for a great number of things – such as items of knowledge – that we would otherwise be tempted to consider purely mental.

The reductionist approach applies what is known as “Occam’s Razor”, named after the 14th century English philosopher William of Ockham. The rule states that if we are faced with two explanations that seem to explain certain situation, and be able to predict it, equally well, we should favour the simplest of the two as the most probable. For instance, if I am faced with two explanations of gravity which are equally successful, but one of them adds, “…and because the Big Giant Pixie wills it”, I may reject that explanation as superfluous. In a similar way, the supposition that there exist mental events and a separate mental substance is regarded by behaviourists as an unnecessary addition because describing observable physical behaviour does just as good a job. To use Gilbert Ryle’s phrase, the “ghost in the machine” is unnecessary because an explanation of how the machine works is sufficient.