DEFENSE

...having examined and understood everything belonging to this art, anyone will be able to reason and dismantle all the arguments brought against it. Without these principles, all efforts are vain and useless, and one must necessarily grope in the dark. Therefore, one must strive with all their strength to explain and uncover, as exactly as possible, this most excellent part of this art—hidden until now and never handed down by the ancients.

Concerning the matter closest to gold and silver according to the art.

But first, we must define the matter closest to silver and gold according to the art—that which is immediately perfected into silver or gold by the efficient cause the force or agent that triggers a change without any other intervening transformation. This substance is the individual a specific instance of a substance of the silver or gold species that is "about to be." It is not yet silver or gold in act actualized, physical form, but only in proximate potential ready and able to become the thing immediately, which will take on the form of one or the other as soon as it is moved by the efficient cause.

What an individual is.

For an "individual" is that which possesses properties that, taken together, can never be attributed to many different things. These properties do not constitute the specific difference the core characteristic that defines a species but only provide the aptitude and readiness to take on the next form. For example, consider "dog seed" original: "semen caninum"; in historical biology, "seed" referred to the reproductive essence of a living thing, which has the property of producing a dog in the very next stage of its development. This property will never exist in "horse seed" unless it first undergoes many stages of decay and transformation into dog seed—if such a thing were even possible.

In the same way, the matter closest to silver and gold has this property within the art: that with only a little assistance, it can be changed into them. This property will never exist in any other matter. For this is an inviolable law of nature: no individual of one species can ever pass into an individual of another species unless it first possesses the property and potential closest to that second state. That is, it must first be an individual with the proximate potential to become the species that is about to arise.

The material cause in mines is not the proximate matter of the art.

The proximate matter in nature is unknown.

To investigate this matter as it exists in natural mines, and to subject it to the efficient cause so that it may act upon it and complete its work, is impossible. Indeed, it is a rule that nothing can reach the power of the intellect that was not first perceived by the senses. But the proximate matter the immediate "raw material" deep beneath the earth, from which nature alone produces silver and gold, is unknown to our senses. Even the serious authors who have written on this subject do not agree on what that proximate matter is in nature; indeed, they disagree, and each defends his own opinion with probable reasons, though not with absolute proofs. Even if it were granted that the matter...