The second case is that one knows that this alignment between the earth, moon, and sun must occur, and that it occurs only under certain conditions. This is universal knowledge, which yields no knowledge of any eclipse that actually occurs.

It may then be said: Such knowledge is impossible without knowledge of particular eclipses. For eclipses are caused by the movements of specific bodies at determinate times. Knowledge of all these causes entails knowledge of every particular eclipse—before, during, and after its occurrence. Thus, given knowledge of the causes of events, universal knowledge is inconceivable without knowledge of the particulars that actually occur. Otherwise, knowledge of all the causes would not have been attained.

This is why, since we do not know most causes, we do not know what will happen. When we know the causes of something, however, we know of its occurrence before it happens, while it happens, and afterward. Consider someone who knew that Muhammad, may Allah bless him and grant him peace, would be sent as a prophet, and that he would be sent when certain things occurred. If that person knew that those things had not occurred, he would know that Muhammad had not yet been sent; if he knew that they had occurred, he would know that Muhammad had been sent.

In much of what people discuss on the basis of preliminary knowledge, they have learned only part of the cause, without knowing the complete cause or what might prevent its effect. They are therefore sometimes right, but more often wrong, because what they do not know about the complete cause and its impediments exceeds what they know.

Ibn Sīnā’s statement has already been cited:

“Universals may be intellectually apprehended insofar as they necessarily follow from their causes, as related to a principle whose kind is particularized by whoever singles it out.”

He said in his commentary:

“That is, those particulars are rendered specific by the nature of that