50 Years ago

My Philosophical Development. By Bertrand Russell — All those whose study of philosophy is grounded in the empirical tradition regard Lord Russell as the greatest living philosopher ... Although one should not neglect other influences ... there is no doubt that the main responsibility for the present state of philosophy lies squarely on Russell's shoulders ... There are few philosophers in history who have written important philosophical works almost continuously for fifty years: Russell has added to the immense debt we owe him by now giving us a full-scale account of his philosophical development, written with all the clarity, verve and wit we are accustomed to expect from anything he writes.

From Nature 12 September 1959.

100 Years ago

Organic Memory. By Prof. Richard Semon — The theory of the Mneme, propounded by Prof. Semon, has attracted the attention both of psychologists and of those naturalists who are interested in the profound problems of hereditary transmission. It is founded on the statement, which everyone is ready to admit, that a stimulus must affect the quality of living matter in such a way that the matter is not the same as it was before the stimulus acted. A permanent change, which, in a sense, may be called a memory, has been effected, or, to use the terminology invented by Semon, the action has been engraphic and the change itself is an engram ... All stimuli then produce engrams, and the sum of the engrams of a living being is its mneme ... Thus a stimulus may produce effects which radiate from the organised matter first affected to organised matter throughout the whole organism, either by nerve paths or by proplasmic intercellular filaments, and in this way faint engrams may be made on the matter of the reproductive elements, ova or spermatozoids.

From Nature 9 September 1909.