Page:Landmarks of Scientific Socialism-Anti-Duehring-Engels-Lewis-1907.djvu/35

 to the molecular weights, under the same temperature, heat takes its place directly in the series of such measurable forms of motion. Ten years ago the newly discovered great fundamental law of motion was still understood as a mere law of the conservation of energy, as a mere expression of the indestructibility and uncreatibility of motion, and therefore merely on its quantitative side. That narrow negative expression has been more and more subordinated to the transformation of energy, in which the qualitative content of the process is duly recognised and the last notion of an extramundane Creator is destroyed. That the quantity of motion (of energy, so called) is not changed when it is transformed into kinetic energy (mechanical force, so called), into electricity, heat, potential static energy need not now be preached any longer as something new, it served as the foundation, once attained, of many valuable investigations of the process of transformation itself, of the great fundamental process, in the knowledge of which is comprehended the knowledge of all nature. And since biology has been treated in the light of the theory of evolution it has abolished one stiff line of classification after another in the realm of organic nature. The entirely unclassified intermediate conditions increase in number every day. Later investigations throw organisms out of one class into another, and marks of distinction which have become articles of faith lose their individual reality. We have now mammals which lay eggs and, if the news is established, birds also which go on all fours. It was already observed, before the time of Virchow, as a conclusion of the discovery of the cell, that the identity of the individual creature is lost, scientifically and dialectically speaking, in a federation of cells, so the idea of animal (and therefore human)