In preparing lead plaster by boiling olive oil with oxide of lead and a little water - a process palpably analogous to that of the soap-boilerhe obtained a sweet substance which, called by himself " Olsiiss " (" principium dulce oleorum "), is now known as " glycerin."
But the difficulties which embarrassed a former age in trying to conceive the mode in which the universal exists in the individual reappear in the systems of the present period as the problem of the principium individuationis.
He thought, in consequence, that the principium individuationis, which differentiates two members of the kind, e.g.
There is indeed a sense in which all inference is from ground to consequence, because it is from logical ground (principium cognoscendi) to logical consequence.
In all induction, as Aristotle said, the particulars are the evidence, or ground of our knowledge (principium cognoscendi), of the universal.