Thus arose in the eighteenth and nineteenth centuries the dogma of the fixity of species—a dogma based, it is true, on a direct appeal to fact as well as to conscience. But this dogma contained the germ of its own undoing, in so far as it appealed for its support to observations that every man might make for himself. Yet so influential were its advocates, so convinced of its truth, that more than one assault was made before it crumbled away.
It is no small pleasure to repeat to-day the names of those bold and original thinkers, who braved the displeasure of their compatriots and the contempt of their times, who brought forward evidence and argument to disprove the teaching of the schools. Their work, it is true, failed in the sense that it received no sufficient meed of praise or word of commendation, but who will deny that a seed was sown that in time bore fruit? Foremost, I think, ranks the great Lamarck, the centenary of whose "Philosophic Zoologique" is celebrated this year in France—a bold spirit, whose ideas, based on a wide familiarity with facts, live and bear fruit to-day. Geoffroy St. Hilaire, advanced thinker and philosopher of nature, opponent of the great anatomist Cuvier, brought the problem of evolution to the bar of judgment, losing the decision, it is true, but his ideas a later generation hold in high esteem. Erasmus Darwin, grandfather of our Darwin, author of "The Zoonomia," celebrated in verse "The Botanic Garden" and the "Loves of the Plants," and even before Lamarck, advocated the principle of evolution and theof inheritance of acquired characters. Herbert Spencer, adopting the idea of evolution, laid thereon the elaborate superstructure of his philosophy. Robert Chambers, too, kept alive the central idea of change in the organic world in his "Vestiges of Creation." Others there were, besides, in different lands, but these especially were nearer to Darwin and his times.
We come now to the years between 1837 and 1844, when Darwin was making his memorable notes on the relation between varieties and species. Reading through his letters of this period one is surprised to find how little he was impressed by the history of zoology and the influences of his own time, and how much he based his conclusions on the results of his own close observations, his accumulation of data, and careful consideration of facts. In regard to Lamarck, Darwin states in his autobiography, that in 1835 when he was at Edinburgh University, Dr. Grant "burst forth in high admiration of Lamarck and his views on evolution. I listened in silent astonishment, and as far as I can judge, without any effect on my mind."
In later years, after reading Lamarck, Darwin wrote Lyell, in 1859: