If I rest my system of cosmogony on the former, preferably to the latter, it is at my choice.

The matter seems entirely arbitrary.

And when CLEANTHES asks me what is the cause of my great vegetative or generative faculty, I am equally entitled to ask him the cause of his great reasoning principle.

These questions we have agreed to forbear on both sides; and it is chiefly his interest on the present occasion to stick to this agreement.

Judging by our limited and imperfect experience, generation has some privileges above reason: for we see every day the latter arise from the former, never the former from the latter.
Compare, I beseech you, the consequences on both sides.