A particular dubious debating tactic is to build up a strawman - that is to falsely attribute to your opponent a position - and then to hack away at it. Such was the case with Keynes's 'restating' of Saye's law, that supply creates demand. This not what Saye was saying. What saye was really saying was that supply of x constitutes demand for y. and you see this in Earth. if you have a bunch of bushels, and you sell them, you are going to use this revenue to buy other stuff. A supply of bushels constitutes a demand for troops, or turrets, or tech, or oil. This is why there is no such thing as a 'general glut'.