An ancient compendium of ancient philosophy. Placita (Tenets), generally attributed to an author named Aëtius and dating from the late first or early second century AD, was a compendium setting out in summary fashion the principal doctrines and opinions of philosophers and philosophical schools in response to questions and topics in the domain of natural philosophy. Now lost, Placita can be largely reconstructed from the work of three authors working in the period from the second to the fifth century (Pseudo-Plutarch, Stobaeus, and Theodoret) who quote from it extensively. Placita is...