superior and things inferior. Thus you will obtain the glory of the
whole world, and obscurity will fly away from you."

This sentence evidently teaches the unity of things in heaven and
things on earth, and asserts the possibility of gaining, not merely a
theoretical, but also a practical, knowledge of the essential
characters of all things. Moreover, the sentence implies that this
fruitful knowledge is to be obtained by examining nature, using as
guide the fundamental similarity supposed to exist between things
above and things beneath.

The alchemical writers constantly harp on this theme: follow nature;
provided you never lose the clue, which is simplicity and similarity.

The author of _The Only Way_ (1677) beseeches his readers "to enlist
under the standard of that method which proceeds in strict obedience
to the teaching of nature ... in short, the method which nature
herself pursues in the bowels of the earth."

The alchemists tell us not to expect much help from books and written
directions. When one of them has said all he can say, he adds--"The
question is whether even this book will convey any information to one
before whom the writings of the Sages and the open book of Nature are
exhibited in vain." Another tells his readers the only thing for them
is "to beseech God to give you the real philosophical temper, and to
open your eyes to the facts of nature; thus alone will you reach the
coveted goal."

"Follow nature" is sound advice. But, nature was to be followed with
eyes closed save to one vision, and the vision was to be seen before