And if the matter of the Philosophers Stone, and the manner of preparing it, be such Mysteries as they would have the World believe them, they may Wr… - Robert Boyle

I find that even Eminent Writers (such as Raymund Lully, Paracelsus, and others) do so abuse the termes they employ, that as they will now and then give divers things one name, so they will oftentimes give one thing, many Names; and some of them (perhaps) such, as do much more properly signifie some Distinct Body of another kind; nay even in Technical Words or Termes of Art, they refrain not from this Confounding Liberty; but will, as I have Observ'd call the same Substance, sometimes the Sulphur, and Sometimes the Mercury, of a Body.

Among Latin writers, the acceptations of the word nature are so many, that I remember, one author reckons up no less than fourteen or fifteen. Hence we see how easy 'tis for the generality of men, without excepting those who write of natural things, to impose upon others and themselves, in the use of a word so apt to be mis-employ'd. ..the very great ambiguity of this term, and the promiscuous use made of it, without sufficiently attending to its different significations, render many of the expressions wherein 'tis employ'd either unintelligible, improper, or false.

Epicurus... supposes not only all mixt bodies, but all others to be produced by the various and casual occursions of atoms, moving themselves to and fro by an internal principle in the immense or rather infinite vacuum.