The way, the method, by which this enlightenment is produced, is the special object of our study. We do not deny that cause and effect serve us as a means, but only as one of many. We honor the category of cause and effect far too much when we regard it as _the_ panacea. We have seen that formerly other viewpoints served the same purpose and still others exist today, some of which have a prospect of being valued more highly in the future than cause and effect. This category serves very well for the explanation of processes which follow one another. But there are other phenomena which occur side by side, and these must also be elucidated. For such a purpose, the category of genus and species is quite as serviceable. Haeckel speaks somewhat slightingly of "museum zoologists and herbarium botanists," because they merely classify animals and plants according to genera and species. The modern zoologists and botanists do not simply consider the multiplicity of animals and plants which exist simultaneously, but also the chronological order of the changes and transformations, and in this way they have gained much more of a life-picture of the zoological and botanical world, a picture not alone of its being, but also of its growing, of arising and declining. Undoubtedly the knowledge of the museum zoologists and herbarium botanists was meager, narrow, mechanical, and modern science offers a far better portrait of truth and life. Still this is no reason for overestimating the value of analysis by cause and effect. This method supplements the category of genus and species. It assists in enlightening, it helps in the process of thought, but it does not render other forms of thought superfluous. It is essential for the theory of understanding, to recognize the special forms of thought of old and new times as peculiarities which have a common nature. This common nature of the process of thought, understanding, enlightenment, is a part of the universal world process, and not greatly different from it. The conception of a cause partly explains the phenomena of the universe; but so does the conception of a purpose and of a species, in fact, so do all conceptions. In the universe all parts are causes, all of them caused, produced, created, and yet there is no creator, no producer, no cause. The general produces the special, and the latter in turn produces by reaction the general.