Nevertheless, it may be said to him:
To suppose that a particular motion exists in beginningless eternity and is preceded by another combines two contradictories and is therefore intrinsically impossible. What is intrinsically impossible entails an impossible consequence, so whatever follows from this supposition poses no difficulty.
As for the other supposition—namely, that one of these motions exists in beginningless eternity while being preceded—they answered al-Urmawī by saying that the existence of a particular motion in beginningless eternity is likewise impossible. Since this is impossible, it may entail an impossible consequence: that something beginningless is preceded by something else. Only the kind is beginningless, and it is not preceded by anything else.
Some challenged this objection, saying:
“In that case, none of the motions exists in beginningless eternity, for if it did, it could not cease. Something of this nature cannot be beginningless.”
The answer to this objection is as follows:
None of the particular motions exists in beginningless eternity, since none is without a beginning; rather, each has a beginning. But does their kind have a beginning? That is a different question. The disputant concedes that none of the particular motions is beginningless; his disagreement concerns something else. Likewise, he concedes that none of the particular motions is everlasting, while maintaining that their kind is everlasting.
[The fourth argument and commentary on it]
Al-Rāzī said:
The fourth argument: “Whenever Saturn completes one orbit