superiority of the planets. He placed the seven planets in the
following descending order: Saturn, Jupiter, Mars, Sol, Venus,
Mercury, Luna. "The virtues of the planets descend," he said, "but do
not ascend"; it is easy to change Mars (iron) into Venus (copper), for
instance, but Venus cannot be transformed into Mars.

Although the alchemists regarded everything as influencing, and
influenced by, other things, they were persuaded that the greatest
effects are produced on a substance by substances of like nature with
itself. Hence, most of them taught that the seed of metals will be
obtained by operations with metals, not by the action on metals of
things of animal or vegetable origin. Each class of substances, they
said, has a life, or spirit (an essential character, we might say) of
its own. "The life of sulphur," Paracelsus said, "is a combustible,
ill-smelling, fatness.... The life of gems and corals is mere
colour.... The life of water is its flowing.... The life of fire is
air." Grant an attraction of like to like, and the reason becomes
apparent for such directions as these: "Nothing heterogeneous must be
introduced into our magistery"; "Everything should be made to act on
that which is like it, and then Nature will perform her duty."

Although each class of substances was said by the alchemists to have
its own particular character, or life, nevertheless they taught that
there is a deep-seated likeness between all things, inasmuch as the
power of _the essence_, or _the one thing_, is so great that under its
influence different things are produced from the same origin, and
different things are caused to pass into and become the same thing.
In _The New Chemical Light_ it is said: "While the seed of all things
is one, it is made to generate a great variety of things."