Sabine Hossenfelder argues in her blog \cite{Hossenfelder} that the present situation in foundation of physics should be called not crisis but stagnation. I argue that the main reason of the stagnation is that quantum theory inherited from classical one several notions which should not be present in quantum theory. In particular, quantum theory should not involve the notion of space-time background and, since nature is discrete and even finite, quantum theory should not be based on classical mathematics involving the notions of infinitely small/large and continuity. I discuss uncertainty relations, paradox with observation of stars, symmetry on quantum level, cosmological acceleration, gravity and particle theory. My main conclusion is that the most general quantum theory should be based on finite mathematics and, as a consequence: {\bf Mathematics describing nature at the most fundamental level involves only a finite number of numbers while the notions of limit and infinitely small/large and the notions constructed from them (e.g. continuity, derivative and integral) are needed only in calculations describing nature approximately}.