The consequence of condensation for the relation between latent and manifest dreams is the fact that no simple relations can exist between the elements of the one and the other. A manifest element corresponds simultaneously to several latent ones, and vice versa, a latent element may partake of several manifest ones, an interlacing, as it were. In the interpretation of the dream it also becomes evident that the associations to a single element do not necessarily follow one another in orderly sequence. Often we must wait until the entire dream is interpreted. Dream-work therefore accomplishes a very unusual sort of transcription of dream thoughts, not a translation word for word, or sign for sign, not a selection according to a set rule, as if all the consonants of a word were given and the vowels omitted; nor is it what we might call substitution, namely, the choice of one element to take the place of several others. It is something very different and much more complicated. The second process of the dream-work is _displacement_. Fortunately we are already prepared for this, since we know that it is entirely the work of dream censorship. The two evidences of this are firstly, that a latent element is not replaced by one of its constituent parts but by something further removed from it, that is, by a sort of allusion; secondly, that the psychic accent is transferred from an important element to another that is unimportant, so that the dream centers elsewhere and seems strange. Substitution by allusion is known to our conscious thinking also, but with a difference. In conscious thinking the allusion must be easily intelligible, and the substitute must bear a relation to the actual content. Jokes, too, often make use of allusion; they let the condition of content associations slide and replace it by unusual external associations, such as resemblances in sound, ambiguity of words, etc. They retain, however, the condition of intelligibility; the joke would lose all its effect if the allusion could not be traced back to the actual without any effort whatsoever. The allusion of displacement has freed itself of both these limitations. Its connection with the element which it replaces is most external and remote, is unintelligible for this reason, and if it is retraced, its interpretation gives the impression of an unsuccessful joke or of a forced, far-fetched explanation. For the dream censor has only then accomplished its purpose, when it has made the path of return from the allusion to the original undiscoverable.