Epicycles are predictive, because they just represent a Fourier approximation to an ellipse. They predict the future, just with finite precision, so to increase

Epicycles are predictive, because they just represent a Fourier approximation to an ellipse. They predict the future, just with finite precision, so to increase precision you need to add more parameters. Regarding dark matter, I'm not comparing it to epicycles. The cold dark matter theory is very predictive and it has made many predictions that were confirmed. But in the same time, I am perfectly willing to accept other theory which will explain all current observations without dark matter. Just so far nobody came up with one.