  Hence the debate has typically focused on the contrast between the “the Middle Period dialogues” and “the Late dialogues.”  Revisionists say that the Middle Period dialogues enounce positive doctrines, above all the theory of Forms, which the Late dialogues criticise, reject, or simply bypass. The main place where Revisionists (e.g., Ryle 1939) suppose that Plato criticises the theory of Forms is in the Parmenides (though some Revisionists find criticism of the theory of Forms in the Theaetetus and Sophist as well). The main places where Revisionists look to see Plato managing without the theory of Forms are the Theaetetus and Sophist.