The limits of philosophical demonstration › What does God know?

The thirteenth discussion concerns divine knowledge of changing particulars. A particular is an individual thing or event, such as this eclipse occurring at this time. A universal description concerns a kind or general pattern. The philosophical difficulty arises when knowledge of a changing event seems to require a change in the knower.

Al-Ghazali reconstructs the issue through an eclipse. Before it occurs, someone can know that it will occur. During it, that person can know that it is occurring. Afterwards, the person knows that it occurred. Human knowledge changes as the event moves from future to present to past. How can God know such an event without undergoing that sequence of changes?

The position he attributes to Ibn Sina needs care. He reports both the claim that God knows particulars in a universal manner and the claim that nothing is hidden from divine knowledge. Merely saying that Ibn Sina's God knows generalities and is ignorant of individuals suppresses the qualification that makes the disagreement philosophically difficult.

Al-Ghazali challenges the adequacy and consequences of the proposed account. His concern is whether it truly preserves knowledge of particular persons and their changing actions. A religious account in which God knows obedience, disobedience, and prophecy must explain that knowledge, rather than replace it with a general knowledge of human types.

The issue is not whether a powerful observer could gather more information. Both sides are discussing knowledge unlike ordinary observation. Their dispute concerns the relation between eternal knowing and temporal objects. The reader has to examine whether an argument has transferred assumptions about our knowledge to God's, and whether the proposed alternative avoids the same difficulty.

This is a useful point at which to slow down. “God knows everything” and “God does not change” are statements a thinker might accept together. Their compatibility still requires explanation when what is known changes. Al-Ghazali's critique targets the offered explanation; repeating either statement does not resolve the tension.