Darwin investigated the numerous facts obtained by naturalists in living nature and analysed them through the prism of practical experience.
Darwin himself recorded the fact that he accepted the Malthusian idea.
Darwin himself, in his day, was unable to fight free of the theoretical errors of which he was guilty. It was the classics of Marxism that revealed those errors and pointed them out.
The classics of Marxism, while fully appreciating the significance of the Darwinian theory, pointed out the errors of which Darwin was guilty. Darwin's theory, though unquestionably materialist in its main features, is not free from some serious errors.