All supposedly rational prophesy is fallacious for men and nature being capable of novelty.
That is the thesis of The Poverty of Historicism, that men have free will, which foundations are developed in The Open Society and Its Enemies.
One must dig a little deeper into quantum mechanics and cosmology for the reasonable observation that nature is capable of novelty. In Popper's terms, determinism and reductionism are fallacious. Smolin calls it The Cosmological Fallacy, trying to attribute the Newtonian Principle to reality.