Unlike the Idea of Polarity, of which we treated in the last Book, these Ideas have been current in men's minds from very early times, and formed the subject of some of the first speculations of philosophers. It happened however, as might have been expected, that in the first attempts they were not clearly distinguished from other notions, and were apprehended and applied in an obscure and confused manner. We cannot better exhibit the peculiar character and meaning of these Ideas than by tracing the form which they have assumed {4} and the efficacy which they have exerted in these successive essays. This, therefore, I shall endeavour to do, beginning with the Idea of Element. 2. That bodies are composed or made up of certain parts, elements, or principles, is a conception which has existed in men's minds from the beginning of the first attempts at speculative knowledge. The doctrine of the Four Elements, Earth, Air, Fire and Water, of which all things in the universe were supposed to be constituted, is one of the earliest forms in which this conception was systematized; and this doctrine is stated by various authors to have existed as early as the times of the ancient Egyptians[1\6]. The words usually employed by Greek writers to express these elements are ἀρχὴ a _principle_ or _beginning_, and στοιχεῖον, which probably meant a _letter_ (of a word) before it meant an _element_ of a compound. For the resolution of a word into its letters is undoubtedly a remarkable instance of a successful analysis performed at an early stage of man's history; and might very naturally supply a metaphor to denote the analysis of substances into their intimate parts, when men began to contemplate such an analysis as a subject of speculation. The Latin word _elementum_ itself, though by its form it appears to be a derivative abstract term, comes from some root now obsolete; probably[2\6] from a word signifying _to grow_ or _spring up_. [Note 1\6: Gilbert's _Phys._ 1. i. c. iii.] [Note 2\6: Vossius _in voce_. "Conjecto esse ab antiqua voco _eleo_ pro _oleo_, id est _cresco_: a qua signiflcatione proles, _suboles_, _adolescens_: ut ab _juratum_, _juramentum_; ab _adjutum_, _adjumentum_: sic ab _eletum_, _elementum_: quia inde omnia crescunt ac nascuntur."]