and the sea turning into mercury, the entire population of a town dying in a single instant, or all children becoming learned sages in the very same moment.

Upon this answer they place great reliance, as is cited by Qadi Abu Bakr, Qadi Abu Ya‘la, Abu al-Ma‘ali, al-Razi, and others. They maintain that the intellect yields self-evident certainties: knowledge of the obligatoriness of what is obligatory, the impossibility of what is impossible, and the permissibility of what is permissible. Impossibilities, in their reckoning, include such things as the Tigris turning into blood and other like matters tied to the normal order of the world. In consequence, they sometimes declare customary events to be necessary and at other times to be impossible, even though no cause compels either judgment.

They further say: “We know that this particular matter is permissible and possible, that it depends on no cause and faces no impediment like the other; yet we also know that this one does occur, while that one never occurs, solely on account of custom." Yet, according to them, there is no criterion governing a breach of custom: every departure from the ordinary course qualifies as a miracle for the prophets and may just as well be granted to a saint or to a sorcerer. The difference between the two, in their view, is merely the presence of a prophetic challenge or the absence of an opposing wonder.

The same position is held by the irreligious philosophers who assert that the causes of these signs are celestial forces, psychic forces, and natural forces—causes that, according to them, are equally accessible to prophets and sorcerers. The only distinction, they say, is that a prophet seeks good and justice, whereas a sorcerer seeks evil and oppression.