Universal Lawmaker

There are mathematicians so impressed by the laws of the universe, that they assume a lawmaker or 'god'. This has one seemingly insuperable difficulty. If a prior, or external. lawmaker is required, then by what laws does or did the lawmaker operate. If they were not created by yet another lawmaker, then they were in some way natural. In that case the universe may as well have natural law, and no lawmaker.
The total universe is everything that exists, having present or past influence, one part on another. Anything outside that universe does not exist for it. One part may have evolved out of a previous part, or another part that still exists. Creation is therefore not relevant. The explanation of any part involves the explanation for the whole. Any concept of 'god' involves immanence, or simply natural universal laws. Bearing in mind that the explanation for simple matter is not the explanation for conscious mind.