Now the fundamental substance, common to all, was air. Air was infinite, eternal, powerful; it was, besides, full of intelligence and knowledge. This latter property Diogenes proved by the succession of climatic and atmospheric phenomena of winter and summer, night and day, rain, wind, and fine weather. All these successions were disposed in the best possible manner by the air: which could not have laid out things in such regular order and measure, unless it had been endowed with intelligence. Moreover, air was the source of life, soul, and intelligence, to men and animals: who inhaled all these by respiration, and lost all of them as soon as they ceased to respire.[184] [Footnote 184: Diog. Apoll. Fr. iv.-vi. c. 36-42, Panz.--[Greek: Ou) ga\r a)\n ou(/tô de/dasthai oi(=o/n te ê)=n a)/neu noê/sios, ô(/ste pa/ntôn me/tra e)/chein, cheimô=no/s te kai\ the/reos kai nukto\s kai\ ê(me/rês kai\ u(etô=n kai\ a)ne/môn kai\ eu)diô=n. kai\ ta\ a)/lla ei)/ tis bou/letai e)nnoe/esthai, eu(/riskoi a)\n ou(/tô diakei/mena, ô(s a)nusto\n ka/llista. E)/ti de pro\s tou/tois kai\ ta/de mega/la sêmei=a; a)/nthrôpos ga\r kai\ ta\ a)/lla zô=a a)napne/onta zô/ei tô=| a)e/ri. Kai\ tou=to au)toi=s kai\ psuchê/ e)sti kai\ no/êsis---- --Kai\ moi\ doke/ei to\ tê\n no/êsin e)/chon ei)=nai o( a)ê\r kaleo/menos u(po\ tô=n a)nthrô/pôn], &c. Schleiermacher has an instructive commentary upon these fragments of the Apolloniate Diogenes (Vermischte Schriften, vol. ii. p. 157-162; Ueber Diogenes von Apollonia).] [Side-note: Air possessed numerous and diverse properties; was eminently modifiable.] Air, life-giving and intelligent, existed everywhere, formed the essence of everything, comprehended and governed everything. Nothing in nature could be without it: yet at the same time all things in nature partook of it in a different manner.[185] For it was distinguished by great diversity of properties and by many gradations of intelligence. It was hotter or colder--moister or drier--denser or rarer--more or less active and movable--exhibiting differences of colour and taste. All these diversities were found in objects, though all at the bottom were air. Reason and intelligence resided in the warm air. So also to all animals as well as to men, the common source of vitality, whereby they lived, saw, heard, and understood, was air; hotter than the atmosphere generally, though much colder than that near the sun.[186] Nevertheless, in spite of this common characteristic, the air was in other respects so indefinitely modifiable, that animals were of all degrees of diversity, in form, habits, and intelligence. Men were doubtless more alike among themselves: yet no two of them could be found exactly alike, furnished with the same dose of aerial heat or vitality. All other things, animate and inanimate, were generated and perished, beginning from air and ending in air: which alone continued immortal and indestructible.[187]