DRIESCH, HANS ), German biologist and phi losopher, was born on Oct 28, 1867, at Kreuznach. After study ing at Hamburg, Freiburg, Munich and Jena, he travelled in the Far East, and from 1891 to 190o worked in the zoological sta tion of Naples. He then settled in Heidelberg where in 1909 he became privat-docent and in 1911 professor of philosophy. In 19 20 he was made professor at Cologne and in 1921 at Leipzig. Driesch began as a disciple of Haeckel but through the influence of G. Wolff and W. Roux came to support a dynamic vitalism.
His doctrine that the functions of protoplasm cannot be ex plained mechanically was the outcome of experiments on the blastula of the sea-urchin, which showed that any fragment cut at random always gave a complete embryo and on the restitution of animal parts. From these he concluded that the organism must be a harmonious equipotential system possessing a vital indi vidualizing entelechy which works through the matter with a view to the whole. He also maintained that instinct and action are inexplicable mechanically. His anti-mechanism in the psychologi cal sphere is seen in his Leib and Seele (Leipzig, 192o. Eng. trans. with a full bibliography of his works, 1927). His other important works are Analytische Theorie der organischen Entwicklung (Leipzig, 1894) ; Science and Philosophy of the Organism (Gif ford Lectures, 1907-8) ; History and Theory of Vitalism (1914) ; The Problem of Individuality (1914); Wissen and Denken (Leipzig, 1919) ; The Crisis in Psychology (Princeton Lectures,