Abstract

IT has been some time now since anyone professing himself to be a phenomenalist has characterized physical objects as ‘logical constructions out of sense-data’ in the strict sense of this expression. If he is to be justified in applying the expression in the strict sense, the phenomenalist must demonstrate that there exists a relation of mutual entailment between a statement implying the existence of a physical object and a statement referring exclusively to our ‘sense-experiences’. As a matter of historical fact, no phenomenalist has ever succeeded in doing this; and it is now generally acknowledged, even by those who still wish to adhere to some form of a phenomenalistic analysis of physical object statements, that there are difficulties in principle why the reductivist programme of the early phenomenalists cannot be carried out. The modern-day phenomenalist, in an attempt to avoid the pitfalls in his predecessors’ position, tends to regard physical objects as fruitful and convenient theoretical constructions for interpreting and predicting our sense-experiences. Thus, although still committed to the view that physical objects are ‘constructed’ out of sense-data, he is no longer committed to the thesis of a strict logical equivalence between statements about objects and statements about experiences. Professor A J Ayer, perhaps the foremost exponent of this type of view today, put the matter this way not so long ago