4. The highest stage consists of intentionally reuniting images in order to make novel combinations from them. This may be called an active synthesis, and is the true creative imagination. Is this sometimes found in the animal kingdom? Romanes very clearly replies, no; and not without offering a plausible reason. For creation, says he, there must first be capacity for abstraction, and, without speech, abstraction is very weak. One of the conditions for creative imagination is thus wanting in the higher animals. We here come to one of those critical moments, so frequent in animal psychology, when one asks, Is this character exclusively human, or is it found in embryo in lower forms? Thus it has been possible to support a theory opposing that of Romanes. Certain animals, says Oelzelt-Newin, fulfill all the conditions necessary for creative imagination--subtle senses, good memory, and appropriate emotional states.[36] This assertion is perhaps true, but it is purely dialectic. It is equivalent to saying that the thing is possible; it does not establish it as a fact. Besides, is it very certain that all the conditions for creative imagination are present here, since we have just shown that there is lack of abstraction? The author, who voluntarily limits his study to birds and the construction of their nests, maintains, against Wallace and others, that nest-building requires "the mysterious synthesis of representations." We might with equal reason bring the instances of other building animals (bees, wasps, white ants, the common ants, beavers, etc.). It is not unreasonable to attribute to them an anticipated representation of their architecture. Shall we say that it is "instinctive," consequently unconscious? At least, may we not group under this head, changes and adaptations to new conditions which these animals succeed in applying to the typical plans of their construction? Observations and even systematic experiments (like those of Huber, Forel, _et al._) show that, reduced to the alternative of the impossibility of building or the modification of their habits, certain animals modify them. Judging from this, how refuse them invention altogether? This contradicts in no way the very just reservation of Romanes. It is sufficient to remark that abstraction or dissociation has stages, that the simplest are accessible to the animal intelligence. If, in the absence of words, the logic of concepts is forbidden it, there yet remains the logic of images,[37] which is sufficient for slight innovations. In a word, animals can invent according to the extent that they can dissociate. In our opinion, if we may with any truthfulness attribute a creative power to animals, we must seek it elsewhere. Generally speaking, we attribute only a mediocre importance to a manifestation that might very well be the proper form of animal fancy. It is purely motor, and expresses itself through the various kinds of play.