It can be stated without fear of refutation that every physiological investigation shows with accumulating emphasis that the manifestations of living matter are not explicable with only the forces of dead matter, and the more profound the knowledge of the investigator the more certain is the testimony that the life energy is not a mere name.

The Processes of Life Revealed by the Microscope: A Plea for Physiological Histology, Science, N.S. Volume 2, Number 34, August 23, 1895 (p. 210)