Such was the metaphysical or logical foundation of the philosophy of Herakleitus: the idea of an eternal process of change, manifesting itself in the perpetual destruction and renovation of particular realities, but having itself no reality apart from these particulars, and existing only in them as an immanent principle or condition. This principle, from the want of appropriate abstract terms, he expressed in a variety of symbolical and metaphorical phrases, among which Fire stood prominent.[91] But though Fire was thus often used to denote the principle or ideal process itself, the same word was also employed to denote that one of the elements which formed the most immediate manifestation of the principle. In this latter sense, Fire was the first stage of incipient reality: the second stage was water, the third earth. This progression, fire, water, earth, was in Herakleitean language "the road downwards," which was the same as "the road upwards," from earth to water and again to fire. The death of fire was its transition into water: that of water was its transition partly into earth, partly into flame. As fire was the type of extreme mobility, perpetual generation and destruction--so earth was the type of fixed and stationary existence, resisting movement or change as much as possible.[92] Water was intermediate between the two. [Footnote 91: See a striking passage cited from Gregory of Nyssa by Lassalle (vol. i. p. 287), illustrating this characteristic of fire; the flame of a lamp appears to continue the same, but it is only a succession of flaming particles, each of which takes fire and is extinguished in the same instant: [Greek: ô(/sper to\ e)pi\ tê=s thrualli/dos pu=r tô=| me\n dokei=n a)ei\ to\ au)to\ phai/netai--to\ ga\r suneche\s a)ei\ tê=s kinê/seôs a)dia/spaston au)to\ kai\ ê(nôme/non pro\s e(auto\ dei/knusi--tê=| de\ a)lêthei/a| pa/ntote au)to\ e(auto\ diadecho/menon, ou)de/pote to\ au)to\ me/nei--ê( ga\r e)xelkusthei=sa dia\ tê=s thermo/têtos i)kma\s _o(mou= te e)xephlogô/thê kai\ ei)s lignu\n e)kkauthei=sa metapoiê/thê_], &c.] [Footnote 92: Diogen. Laert. ix. 9; Clemens Alexand. Strom. v. 14, p. 599, vi. 2, p. 624. [Greek: Puro\s tropai\ prô=ton tha/lassa, thala/ttês de\ to\ me\n ê(/misu gê=, to\ d' ê(/misu prêstê/r]. A full explanation of the curious expression [Greek: prêstê/r] is given by Lassalle (Herakl. vol. ii. p. 87-90). See Brandis (Handbuch der Gr. Philos. sect, xliii. p. 164), and Plutarch (De Primo Frigido, c. 17, p. 952, F.). The distinction made by Herakleitus, but not clearly marked out or preserved, between the _ideal fire_ or universal process, and the _elementary fire_ or first stage towards realisation, is brought out by Lassalle (Herakleitos, vol. ii. p. 25-29).] [Side-note: Sun and stars--not solid bodies but meteoric aggregations dissipated and renewed--Eclipses--[Greek: e)kpu/rôsis], or destructions of the Kosmos by fire.]