In contradistinction to all this let us remember the rule, valid for psychology as well as for any other science, that we cannot understand the complex phenomena, before we have become familiar with the simple ones, which presuppose the former. Now the general phenomena of the course of simple processes in consciousness, as we have seen them in their most concrete form and under the simplest conditions in our observations of the combination and comparison of rows of beats, give us the most general preliminary conditions, which must be held as a criterion for much more complicated thought-processes. It is evident, however, that these formal conditions of all processes of consciousness cannot be sufficient to account for the special characteristics and phenomena of the development of thought. To do this we must turn our attention to this development itself, as it is shown in the documents of the spoken expression of thought at different stages of consciousness. It is unfortunate that in these and in other cases the development of the child, that is for us the easiest to observe, can give, as is obvious, only a few and in part only doubtful results. The speech and thought of the child, under the present conditions of culture, not only presuppose a number of inherited dispositions, whose influences can scarcely be accurately traced, but it is also absolutely impossible to withdraw the child from the influences to which, from the very beginning, its environment gives rise. Therefore the mental development of our children is under all circumstances not only an accelerated but also in many respects an essentially changed one, in comparison to a purely spontaneous development. On the other hand there are, at least in a relative manner, such stages of a spontaneous development of thinking, in many cases relatively independent of outward influences of culture, in the mental life of more primitive peoples. The different stages, which this mental life shows, find their most adequate expression in the outward phenomena of this mental life itself, and above all in those of speech, which is a means of expression and an instrument of thought at the same time. We can by means of the different stages of the development of speech follow that gradual transition of associative into apperceptive processes of consciousness from step to step. The example given above of a relatively primitive form of spoken thought shows the relation in which it stands to our languages of culture. A closer investigation of this subject would lead us beyond the scope of individual psychology into that of racial psychology, where the most important part deals with the psychological development of thought and speech. CHAPTER V THE LAWS OF PSYCHICAL LIFE