I Want to discuss and illustrate in this paper certain fallacies which we are all very liable to commit in our thinking about political and social questions. Perhaps “thinking” is rather too high-sounding a name to attach to the mental processes which lie behind most political talk. It is at any rate thinking of a very low grade, for a considerable proportion of such discussion in Press and Parliament and private conversation hardly rises above the intellectual level of disputes between boys at a preparatory school.

I have chosen my topic for this evening with an eye to something rather more than its intrinsic philosophical interest. Modern man, as we are all painfully aware, is facing a crisis of peculiar gravity. Perhaps the odds are not so very heavy against a third world war followed by world collapse into anarchy and barbarism. At such a time the philosopher is bound to ask himself whether there is no contribution which his science can make towards the succour of civilization.

It seems to me certain that the perception of foreign bodies of a certain sort, although a necessary, is not the only, part of the basis of our belief in other persons. The greatest disagreement with this view that I know of has been expressed by Professor Aaron in a paper published in Philosophy, XIX, 72. He claims that, since one does not really know “what it means to be a mind in one's own case,” the question whether we can be certain that there are other minds is meaningless except as reducible to the question whether such propositions as “Robinson exists” are propositions which we can be certain about. And he tries to show that no more is involved in the analysis of “Robinson exists” than would be involved in the analysis of propositions of whose truth we can be perceptually certain, such as “That table over there exists” or “The Eiffel Tower exists.” My assurance that Robinson exists is not the assurance that something called Robinson's mind exists. It is the perfectly ordinary perceptual assurance that ‘the person over there’ exists. “You ask me how I am certain that Robinson exists and I answer, ‘Well, look, there he is.’ It would be absurd for anyone to say that he does not exist when I see him here before me and hear him talk and watch him move that chair.”

It is remarkable that we have to-day a number of philosophers who call themselves subjectivists in moral philosophy. For, although the name “subjectivist” is by no means new, philosophers have reserved it hitherto for their opponents, and usually for imaginary opponents at that. Perhaps the chief cause of the change which has taken place in recent years is the discovery of a distinction between descriptive and emotive meaning. In the past the only form of subjectivism considered by writers on moral philosophy was the suggestion that moral sentences such as “You ought to do that” were statements about the speaker's own attitude; and it was easy to refute this by pointing out that we discuss questions of morals in a way which would be unintelligent, and even unintelligible, if moral judgments were only reports of introspection. But those who now call themselves subjectivists maintain that the peculiarity of moral words is their expressive and evocative power. According to their analysis, a speaker who uses one of these words in an indicative sentence may be stating nothing at all, but is undoubtedly trying to influence others (and perhaps also himself) to adopt a certain attitude. This, they say, explains how there can be genuine disagreement about questions of morals and why discussion may produce results. If A tries to evoke one attitude in his hearers and B tries to evoke an incompatible attitude, their utterances are opposed, not indeed like contradictory statements, but rather like the efforts of men engaged in a tug-of-war.