The fact is that our question is actually meaningless because it is interpreted in a metaphysical way: the word "consciousness" (one of the most dangerous terms in modern philosophy) is supposed to stand for content, and this is the reason why it was declared that we could not be absolutely sure of its existence except in our own ego, for did not content require intuition and was not intuition restricted to our own consciousness ? I know that most people find it very difficult to admit that there is no sense in their reasoning, but I must insist that without admitting it we cannot even take the first step in philosophy.
Our "problem" is meaningless, because the word "consciousness" occurs in it in such a way that we cannot possibly express what we mean by it. It is used in such a way that it makes it no discoverable difference in the world whether my fellow creatures are "conscious" beings or not. Whether the answer is "yes" or "no": it cannot be verified and this means that we did not know what we were talking about when we put the question.
It is one of the most important tasks of philosophy to analyse how the word "consciousness" must be interpreted in order make sense in different contents. We know, of course, that some structures must be indicated by it. Keeping this in mind we can easily give a non-metaphysical interpretation to our question: "are animals conscious beings?" If it is to be a real legitimate question it can mean nothing but: "does the behaviour of animals show a certain structure?" Now it has become a genuine problem and can receive a definite answer. The answer is, of course, not given by the philosopher but by the biologist. It is his business to define carefully the kind of structure which comes into question (he will probably describe it in terms of "stimuli" and "responses"), and to state by observation in each case whether a particular animal or human being under particular circumstances exhibits this particular structure. This is an entirely empirical statement to which truth or probability may be ascribed in the same way as to any other expression of a fact. It must be noted that wherever the phrase "a person is conscious (or unconscious)" is used in every day life it has a perfectly good meaning and is verifiable because it expresses nothing but observable facts (which a physician, for instance may enumerate).
It is only on the lips of the metaphysician that the word is employed
