The logic of Keynes' criticism of the Classical model

The Classics' remedy for unemployment was to lower money wages. Keynes opposes this remedy. Therefore, in The General Theory, he aims at building a model in which a fall in money wages may not cause an increase in employment. Most of the interpretations of Keynes identified this aim, but did not attach enough importance to it. Reading The General Theory in the light of this aim, we discover what Keynes' logic of elaboration is, then what Keynes' ideas about voluntary or involuntary unemployment are.