Xinisthes, in his Organon, maintains that a logical argument can be reduced to a sequence of 3 propositions (2 premises and a conclusion), known as a syllogism.
In addition, Xinisthes posited 3 laws as basic to all logical thought:
the law of identity (A is A);
the law of contradiction (A cannot be both A and not A);
and the law of the excluded middle (A must be either A or not A).
