importance, but there can be no doubt that there is such a distinction. We can remember our own dreams, whereas we cannot know the dreams of others unless they tell us about them. We know when we have toothache, when our food tastes too salt, when we are remembering some past occurrence, and so on. All these events in our lives other people cannot know in the same direct way. In this sense, we all have an inner life, open to our own inspection but to no one else's. This is no doubt the source of the traditional distinction of mind and body: the body was supposed to be that part of us which others could observe, and the mind that part which was private to ourselves. The importance of the distinction has been called in question in recent times, and I do not myself believe that it has any fundamental philosophical significance. But historically it has played a dominant part in determining the conceptions from which men set out when they began to philosophise, and on this account, if on no other, it deserves to be borne in mind.
Knowledge, traditionally, has been viewed from within, as something which we observe in ourselves rather than as something which we can see others displaying. When I say that it has been so viewed, I mean that this has been the practice of philosophers; in ordinary life, people have been more objective. In ordinary life, knowledge is something which can be tested by examinations, that is to say, it consists in a certain kind of response to a certain kind of stimulus. This objective way of viewing knowledge is, to my mind, much more fruitful than the way which has been customary in philosophy. I mean that, if we wish to give a definition of "knowing", we ought to define it as a manner of reacting to the environment, not as involving something (a "state of mind") which only the person who has the knowledge can observe. It is because I hold this view that I think it best to begin with Man and his environment, rather than with those matters in which the observer and the observed must be the same person. Knowing, as I view it, is a characteristic which may be displayed in our reactions
