Alexander

For it was he who was at once in the greatest authority, dragging Arrhidaeus around after him to safe-guard, as it were, the royal power. Arrhidaeus was Philip’s son by an obscure and common woman named Philinna, and was deficient in intellect owing to bodily disease. This, however, did not come upon him in the course of nature or of its own accord, indeed, it is said that as a boy he displayed an exceedingly gifted and noble disposition: but afterwards Olympias gave him drugs which injured his body and ruined his mind.