 We want elements to be understood in the sense not of the prime qualities of things, but of the major constituents of natural bodies. For the nature of things is so distributed that the quantity or mass of certain bodies is very great, because their structure requires the texture of an easy and common material…But the quantity of certain other bodies in the universe is small and occurs rarely, because the texture of their matter is very different, very subtle and for the most part delimited and organic; such are the species of natural things, metals, plants, animals. (Bacon 1620, 226)