Footnotes
[1] Platon, from Ancient Greek πλατύς, meaning broad, is probably a nickname, and may possibly even be a ring name, much like how Scott Hall was also known as Razor Ramon or how Ultimate "Ultimate Warrior" Warrior's ring name is Ultimate Warrior. Theories are that the name may refer to the width of his chest and shoulders, to the breadth of his eloquence, or maybe just to the size of his forehead. Possibly it is answer D: all of the above.
[2] "A healthy spirit in a healthy body". The initial saying comes from Juvenalis, a Roman satirist. A similar saying is attributed to Thales, a pre-Socratic philosopher:
τίς εὐδαίμων, "ὁ τὸ μὲν σῶμα ὑγιής, τὴν δὲ ψυχὴν εὔπορος, τὴν δὲ φύσιν εὐπαίδευτος"
Who is happy? "He who has a healthy body, a resourceful mind, and a docile nature."
[3] The evidence, such as it is, is simply that he writes a lot about his family's impressive background. He writes with pride about his father, his stepfather (who was also Plato's mother's uncle), his brothers, sister and stepbrothers. However, a wife is never mentioned. There are some indications that he might have had a mistress at one point, but no definite proof. Incarnated as Lover he is in any case quite bisexual.
[4] Pankration (παγκράτιον, from πᾶν (pan) 'all' and κράτος (kratos) 'power', lit. 'allmight'), also called panmachion or pammachon. Said to be invented either by Herakles or Theseus, it combined boxing with wrestling into what might be called an ancient version of MMA, as it included boxing punches, kicks, and grappling techniques like arm locks, armbars and rear naked chokes.
[5] Just in case: imagine a group of people who have always lived in a cave. They watch shadows pass along the walls as objects pass past a fire lit behind them. These shadows are the prisoner's reality, but they are not 'real'. It is only the philosopher who can understand that they are not real, and may have the chance to go 'outside' - to find the truth, to see the true nature of objects as they are, not mere reflections.
Less well-known is that the allegory extends further. Should a man be freed and enter the outside world, he would look upon the stars, the sun and the moon, and feel the urge to bring his fellow prisoners out of the cave, but would enter it blind once more. The prisoners would therefore consider leaving extremely harmful, and even react with violence should anyone attempt to bring them outside - such perhaps happened to Plato's teacher Socrates, who was brought to trial for his philosophy and was given the death sentence.
[6] In fact, Plato has 'unwritten doctrines' - theories ascribed to him that were only ever shared orally, not written down, because they were considered unfit for wide publication. Because of this they have been considered 'esoteric', which literally means 'inside the walls' and does not necessarily mean a secret doctrine. In the twentieth century, there have been attempts by scholars to attempt to reconstruct these theories, though they remain controversial. Explaining the principles themselves would unfortunately be too much of a digression and is therefore left as an exercise for the reader.
[7] technically a stepladder, really, but who's keeping track, eh?