The greatest part, I should say above two-thirds of the medicinal virtues, consist in the quintessence or occult property of simples, of which we can have no other instruction than use and custom; for quintessence is no other than a quality of which we cannot by our reason find out the cause. In such proofs, those they pretend to have acquired by the inspiration of some daemon, I am content to receive (for I meddle not with miracles); and also the proofs which are drawn from things that, upon some other account, often fall into use amongst us; as if in the wool, wherewith we are wont to clothe ourselves, there has accidentally some occult desiccative property been found out of curing kibed heels, or as if in the radish we eat for food there has been found out some aperitive operation. Galen reports, that a man happened to be cured of a leprosy by drinking wine out of a vessel into which a viper had crept by chance. In this example we find the means and a very likely guide and conduct to this experience, as we also do in those that physicians pretend to have been directed to by the example of some beasts. But in most of their other experiments wherein they affirm they have been conducted by fortune, and to have had no other guide than chance, I find the progress of this information incredible. Suppose man looking round about him upon the infinite number of things, plants, animals, metals; I do not know where he would begin his trial; and though his first fancy should fix him upon an elk's horn, wherein there must be a very pliant and easy belief, he will yet find himself as perplexed in his second operation. There are so many maladies and so many circumstances presented to him, that before he can attain the certainty of the point to which the perfection of his experience should arrive, human sense will be at the end of its lesson: and before he can, amongst this infinity of things, find out what this horn is; amongst so many diseases, what is epilepsy; the many complexions in a melancholy person; the many seasons in winter; the many nations in the French; the many ages in age; the many celestial mutations in the conjunction of Venus and Saturn; the many parts in man's body, nay, in a finger; and being, in all this, directed neither by argument, conjecture, example, nor divine inspirations, but merely by the sole motion of fortune, it must be by a perfectly artificial, regular and methodical fortune. And after the cure is performed, how can he assure himself that it was not because the disease had arrived at its period or an effect of chance? or the operation of something else that he had eaten, drunk, or touched that day? or by virtue of his grandmother's prayers? And, moreover, had this experiment been perfect, how many times was it repeated, and this long bead-roll of haps, and concurrences strung anew by chance to conclude a certain rule? And when the rule is concluded, by whom, I pray you? Of so many