This leading characteristic of dream life--the fact that it takes place in another and more shadowy world and in a different kind of consciousness[2]--has led to the criticism of the study of dreams from the scientific side. We cannot really study our dreams, these objectors say, because we--that is to say, our waking consciousness--cannot come sufficiently closely in contact with them. Dreams, it is argued, are inevitably transformed in our hands; what we are studying is not our dreams, but only our waking, and probably altogether false, impressions of our dreams. There is a certain element of truth in this objection. It is very difficult, indeed impossible, to recall exactly, and in their proper order, even the details of a real adventure which has only just happened to us. It is, obviously, incomparably more difficult to recall an experience which took place, under such shadowy conditions, in a world so remote from the world of waking life. There is, further, the very definite difficulty that we only catch our dreams for a moment by the light, as it were, of the open door as we are emerging from sleep. In other words, our waking consciousness is for a moment observing and interpreting a process in another kind of consciousness, or even if we assert that it is the same consciousness it is still a consciousness that has been working under quite different conditions from waking consciousness, and accepting data which in the waking state it would not accept. For the student of dreams it must ever be a serious question how far the facts become inevitably distorted in this process. Sleeping or waking, it is probable, our consciousness never embraces the whole of the possible psychic field within us. There are, when we are dreaming as well as when we are awake--as will become clearer in the sequel--subconscious, or imperfectly conscious, states just below our consciousness, and exerting an influence upon it.[3] Our latent psychic possessions, among which dreams move, would seem to be by no means always at the same depth; the specific gravity of consciousness, as it were, varies, and these latent elements rise or fall, becoming nearer to the conscious surface or falling further away from it. But the greatest change must take place when the waking surface is reached and the outer world breaks on sleeping consciousness. In that change there is doubtless a process of necessary and automatic transformation and interpretation. We may picture it, perhaps, as somewhat the same process as when a person skilled in both languages takes up a foreign book and reads it out in his own tongue. With practice the reader may become unconscious that he is transforming everything, that the words he utters are different from the words he sees, and that he even transposes their order, sometimes putting in the middle of a sentence the verb he sees at the end.