Paracelsus' extract demonstrates the sort of information pre-18^th century chemists (and indeed, many 18^th century one s as well) had at their disposal to understand make-up of the natural world. In terms of reading this week's reading, it is both simple an difficult.

The difficulty lies in the impenetrability of the ideas that Paracelsus uses to interpret the seven metals. To the modern eye, little makes sense on why certain metals are connected to certain planets or certain properties. And indeed, to the alchemist, there were reasons, but for those who did not know the reasons, it would be unwise to reveal them. And therein lies the central paradox or Catch-22^{[ _1_]} of Paracelsianism: if you already know the secrets, you do not need to be taught, but if you don't know the secrets, it is better not to teach you. Note the closing phrase of this reading; "If you do not yet understand it, or are not practiced therein, it is well. It is better that it should be kept concealed, and not made public." This of course raises the question of where the Paracelsian alchemists learned the secrets. There are three possibilities:

1. A modern skeptic (and indeed many contemporary 16^th and 17^th century ones as well -- see Ben Johnson's play, The Alchemist) would say that no one ever did know the secret and all alchemists were charlatans. This is indeed a possibility.
2. One could convince an alchemist to teach you the secrets, if he were willing. This is also possible, and many "alchemists" did take apprentices.
3. You could discover these ideas for yourself, armed with the general outlines as people like Paracelsus provided. This was obviously one of the more popular routes, given the wide-spread success of books on alchemy. This also appealed to the emergent scientific/experimental culture that was appearing in the later 16^th century.

From here, the rest of this summary will summarize the elements of the cannons of the metals and make a few concluding remarks.