Timaeus is one of Plato's dialogues written in 360 BC. The dialogue is mostly in the form of a long monologue given by the titular character Timaeus of Locri. The work puts forward speculation and philosophy on the nature of the physical world and human beings and is followed by the dialogue Critias. Participants in the dialogue include Socrates, Timaeus, Hermocrates, and Critias. Some scholars believe that it is not the Critias of the Thirty Tyrants who is appearing in this dialogue, but his grandfather, who is also named Critias. It has been suggested that Timaeus influenced a book about Pythagoras, written by Philolaus. Plato's Timaeus is often required textbook reading in various subjects including humanities, philosophy, metaphysics, politics & social sciences, as well as Greek and Roman studies.