Sirius signified certain emanations which caused its malignant influence. Anyone suffering its effects was said to be "star-struck" (, "astrobólētos"). It was described as "burning" or "flaming" in literature. The season following the star's reappearance came to be known as the "dog days". The inhabitants of the island of Ceos in the Aegean Sea would offer sacrifices to Sirius and Zeus to bring cooling breezes, and would await the reappearance of the star in summer. If it rose clear, it would portend good fortune; if it was misty or faint then it foretold (or emanated) pestilence. Coins retrieved from the island
Belief with delineating the boundary between justified belief and opinion, and involved generally with a theoretical philosophical study of knowledge. The primary problem in epistemology is to understand exactly what is needed in order for us to have knowledge. In a notion derived from Plato's dialogue "Theaetetus", where the epistemology of Socrates (Platon) most clearly departs from that of the sophists, who at the time of Plato seem to have defined knowledge as what is here expressed as "justified true belief". The tendency to translate from belief (here: doxa – common opinion) to knowledge (here: episteme), which Plato (e.g. Socrates of