Moreover, one of the effects of condensation upon the relationship between the manifest and the latent dream is that the connection between the elements of the one and of the other nowhere remains a simple one; for by a kind of interlacing a manifest element represents simultaneously several latent ones and, conversely, a latent thought may enter into several manifest elements. Again, when we come to interpret dreams, we see that the associations to a single manifest element do not commonly make their appearance in orderly succession; we often have to wait until we have the interpretation of the whole dream. The dream-work, then, follows a very unusual mode of transcription for the dream-thoughts; not a translation, word for word, or sign for sign; nor yet a process of selection according to some definite rule, for instance, as though the consonants only of the words were reproduced and the vowels omitted; nor again what one might call a process of representation, one element being always picked out to represent several others. It works by a different and much more complicated method. The second achievement of the dream-work is DISPLACEMENT. Fortunately here we are not breaking perfectly fresh ground; indeed, we know that it is entirely the work of the dream-censorship. Displacement takes two forms: first, a latent element may be _replaced_, not by a part of itself, but by something more remote, something of the nature of an allusion; and, secondly, the _accent_ may be transferred from an important element to another which is unimportant, so that the centre of the dream is shifted as it were, giving the dream a foreign appearance. Substitution by allusion is familiar to us in our waking thoughts also, but with a difference; for it is essential in the latter that the allusion should be easily comprehensible, and that the content of the substitute should be associated to that of the thought proper. Allusion is also frequently employed in wit, where the condition of association in content is dispensed with and replaced by unfamiliar external associations, such as similarity of sound, ambiguity of meaning, etc. The condition of comprehensibility, however, is observed: the joke would lose all its point if we could not recognize without any effort what is the actual thing to which the allusion is made. But in dreams allusion by displacement is unrestricted by either limitation. It is connected most superficially and most remotely with the element for which it stands, and for that reason is not readily comprehensible; and, when the connection is traced, the interpretation gives the impression of an unsuccessful joke or of a “forced,” far-fetched and “dragged in” explanation. The object of the dream-censorship is only attained when it has succeeded in making it impossible to trace the thought proper back from the allusion.