Why Post Keynesianism is not yet a science

In a programmatic article Alfred Eichner explained, from a Post Keynesian perspective, why neoclassical economics is not yet a science. This was some time ago and one would expect that Post Keynesianism, with a heightened awareness of scientific standards, has done much better than alternative approaches in the meantime. There is wide agreement that this is not the case. Explanations, though, differ widely. The present – strictly formal – inquiry identifies an elementary logical flaw. This strengthens the argument that the Post Keynesian motto ‘it is better to be roughly right than precisely wrong!’ is methodologically indefensible.