And, moreover, the alchemist's conception of an orderly material universe was so intimately connected with his ideas of morality and religion, that to disprove the possibility of the great transmutation would be to remove not only the basis of his system of material things, but the foundations of his system of ethics also.

To take away his belief in the possibility of changing other metals into gold would be to convert the alchemist into an atheist.
How, then, was the transmutation to be accomplished?
Evidently by the method whereby nature brings to perfection other living things; for the alchemist's belief in the simplicity and unity of nature compelled him to regard metals as living things.
Plants are improved by appropriate culture, by digging and enriching the soil, by judicious selection of seed; animals are improved by careful breeding.

By similar processes metals will be encouraged and helped towards perfection.

The perfect state of gold will not be reached at a bound; it will be gained gradually.

Many partial purifications will be needed.