Chapter VI.--Anaximenes; His System of "An Infinite Air;" His Views of Astronomy and Natural Phenomena.
But Anaximenes, who himself was also a native of Miletus, and son of Eurystratus, affirmed that the originating principle is infinite air, out of which are generated things existing, those which have existed, and those that will be, as well as gods and divine (entities), and that the rest arise from the offspring of this. But that there is such a species of air, when it is most even, which is imperceptible to vision, but capable of being manifested by cold and heat, and moisture and motion, and that it is continually in motion; for that whatsoever things undergo alteration, do not change if there is not motion. For that it presents a different appearance according as it is condensed and attenuated, for when it is dissolved into what is more attenuated that fire is produced, and that when it is moderately condensed again into air that a cloud is formed from the air by virtue of the contraction; [79] but when condensed still more, water, (and) that when the condensation is carried still further, earth is formed; and when condensed to the very highest degree, stones. Wherefore, that the dominant principles of generation are contraries,--namely, heat and cold. And that the expanded earth is wafted along upon the air, and in like manner both sun and moon and the rest of the stars; for all things being of the nature of fire, are wafted about through the expanse of space, upon the air. And that the stars are produced from earth by reason of the mist which arises from this earth; and when this is attenuated, that fire is produced, and that the stars consist of the fire which is being borne aloft. But also that there are terrestrial natures in the region of the stars carried on along with them. And he says that the stars do not move under the earth, as some have supposed, but around the earth, [80] just as a cap is turned round our head; and that the sun is hid, not by being under the earth, but because covered by the higher portions of the earth, and on account of the greater distance that he is from us. But that the stars do not emit heat on account of the length of distance; and that the winds are produced when the condensed air, becoming rarified, is borne on; and that when collected and thickened still further, clouds are generated, and thus a change made into water. And that hail is produced when the water borne down from the clouds becomes congealed; and that snow is generated when these very clouds, being more moist, acquire congelation; and that lightning is caused when the clouds are parted by force of the winds; for when these are sundered there is produced a brilliant and fiery flash. And that a rainbow is produced by reason of the rays of the sun falling on the collected air. And that an earthquake takes place when the earth is altered into a larger (bulk) by heat and cold. These indeed, then, were the opinions of Anaximenes. This (philosopher) flourished about the first year of the lviii. Olympiad. [81]
[79] Or, "revolutionary motion."
[80] Plutarch, in his De Placitis Philosophorum, attributes both opinions to Anaximenes, viz., that the sun was moved both under and around the earth.
[81] [b.c. 556.]
Chapter VII.--Anaxagoras; His Theory of Mind; Recognises an Efficient Cause; His Cosmogony and Astronomy.
After this (thinker) comes Anaxagoras, [82] son of Hegesibulus, [83] a native of Clazomenæ. This person affirmed the originating principle of the universe to be mind and matter; mind being the efficient cause, whereas matter that which was being formed. For all things coming into existence simultaneously, mind supervening introduced order. And material principles, he says, are infinite; even the smaller of these are infinite. [84] And that all things partake of motion by being moved by mind, and that similar bodies coalesce. And that celestial bodies were arranged by orbicular motion. That, therefore, what was thick and moist, and dark and cold, and all things heavy, came together into the centre, from the solidification of which earth derived support; but that the things opposite to these--namely, heat and brilliancy, and dryness and lightness--hurried impetuously into the farther portion of the atmosphere. And that the earth is in figure plane; and that it continues suspended aloft, by reason of its magnitude, and by reason of there being no vacuum, and by reason of the air, which was most powerful, bearing along the wafted earth. But that among moist substances on earth, was the sea, and the waters in it; and when these evaporated (from the sun), or had settled under, that the ocean was formed in this manner, as well as from the rivers that from time to time flow into it. And that the rivers also derive support from the rains and from the actual waters in the earth; for that this is hollow, and contains water in its caverns. And that the Nile is inundated in summer, by reason of the waters carried down into it from the snows in northern (latitudes). [85] And that the sun and moon and all the stars are fiery stones, that were rolled round by the rotation of the atmosphere. And that beneath the stars are sun and moon, and certain invisible bodies that are carried along with us; and that we have no perception of the heat of the stars, both on account of their being so far away, and on account of their distance from the earth; and further, they are not to the same degree hot as the sun, on account of their occupying a colder situation. And that the moon, being lower than the sun, is nearer us. And that the sun surpasses the Peloponnesus in size. And that the moon has not light of its own, but from the sun. But that the revolution of the stars takes place under the earth. And that the moon is eclipsed when the earth is interposed, and occasionally also those (stars) that are underneath the moon. And that the sun (is eclipsed) when, at the beginning of the month, the moon is interposed. And that the solstices are caused by both sun and moon being repulsed by the air. And that the moon is often turned, by its not being able to make head against the cold. This person was the first to frame definitions regarding eclipses and illuminations. And he affirmed that the moon is earthy, and has in it plains and ravines. And that the milky way is a reflection of the light of the stars which do not derive their radiance from the sun; [86] and that the stars, coursing (the firmament) as shooting sparks, arise out of the motion of the pole. And that winds are caused when the atmosphere is rarified by the sun, and by those burning orbs that advance under the pole, and are borne from (it). And that thunder and lightning are caused by heat falling on the clouds. And that earthquakes are produced by the air above falling on that under the earth; for when this is moved, that the earth also, being wafted by it, is shaken. And that animals originally came into existence [87] in moisture, and after this one from another; and that males are procreated when the seed secreted from the right parts adhered to the right parts of the womb, and that females are born when the contrary took place. This philosopher flourished in the first year of the lxxxviii. Olympiad, [88] at which time they say that Plato also was born. They maintain that Anaxagoras was likewise prescient.
[82] Aristotle considers that Anaxagoras was the first to broach the existence of efficient causes in nature. He states, however, that Hermotimus received the credit of so doing at an earlier date.
[83] Or, Hegesephontus.
[84] Simplicius, in his Commentary on Aristotle's Physics, where (book i. c. 2) Anaxagoras is spoken of, says that the latter maintained that "all things existed simultaneously--infinite things, and plurality, and diminutiveness, for even what was diminutive was infinite." (See Aristotle's Metaphysics, iii. 4, Macmahon's translation, p. 93.) This explains Hippolytus' remark, while it suggests an emendation of the text.
[85] Or, "in the Antipodes;" or, "from the snow in Æthiopia."
[86] Or, "overpowered by the sun," that is, whose light was lost in the superior brilliancy of the sun.
[87] Or, "were generated."
[88] [Died b.c. 428 or 429.]