of cannon, that is to say, explains it from _afterwards_ so that he first _thinks_ he experiences the producing circumstances and then that sound. But how does it happen that the mind of the dreamer is always so mistaken, while the same mind when awake is accustomed to be so temperate, careful, and sceptical with regard to its hypotheses? so that the first random hypothesis for the explanation of a feeling suffices for him to believe immediately in its truth? (For in dreaming we believe in the dream as if it were a reality, _i.e._ we think our hypothesis completely proved.) I hold, that as man now still reasons in dreams, so men reasoned also _when awake_ through thousands of years; the first _causa_ which occurred to the mind to explain anything that required an explanation, was sufficient and stood for truth. (Thus, according to travellers' tales, savages still do to this very day.) This ancient element in human nature still manifests itself in our dreams, for it is the foundation upon which the higher reason has developed and still develops in every individual; the dream carries us back into remote conditions of human culture, and provides a ready means of understanding them better. Dream-thinking is now so easy to us because during immense periods of human development we have been so well drilled in this form of fantastic and cheap explanation, by means of the first agreeable notions. In so far, dreaming is a recreation for the brain, which by day has to satisfy the stern demands of thought, as they are laid down by the higher culture. We can at once discern an allied process even in our awakened state, as the door and ante-room of the dream. If we shut our eyes, the brain produces a number of impressions of light and colour, probably as a kind of after-play and echo of all those effects of light which crowd in upon it by day. Now, however, the understanding, together with the imagination, instantly works up this play of colour, shapeless in itself, into definite figures, forms, landscapes, and animated groups. The actual accompanying process thereby is again a kind of conclusion from the effect to the cause: since the mind asks, "Whence come these impressions of light and colour?" it supposes those figures and forms as causes; it takes them for the origin of those colours and lights, because in the daytime, with open eyes, it is accustomed to find a producing cause for every colour, every effect of light. Here, therefore, the imagination constantly places pictures before the mind, since it supports itself on the visual impressions of the day in their production, and the dream-imagination does just the same thing,--that is, the supposed cause is deduced from the effect and represented after the effect; all this happens with extraordinary rapidity, so that here, as with the conjuror, a confusion of judgment may arise and a sequence may look like something simultaneous, or even like a reversed sequence.