On the Incorruptibility of the World (131-135)

let us therefore examine the dates of each of these, disregarding the fables invented by the tragedians about the gods; but if man is not eternal then neither is any other animal, so that then neither are the places which receive them, the earth, or the water, or the air; from all which considerations it is plain that this world is liable to destruction.

but after a long lapse of time the additional growth becomes conspicuous because the trees having a more rapid nature, display their increase with great rapidity; but mountains have a slower character, on which account it happens that the additions which take place in their case are not perceptible by the outward senses except after a long time.

And these men appear to be ignorant of the manner in which they are produced, since if they had not been, perhaps they would have been silent out of shame; but still there is no reason why we should not teach them; but there is nothing new in what is now said, neither are they our words but the ancient sayings of wise men, by whom nothing which was necessary for knowledge has been left uninvestigated;

when the fiery principle which is contained beneath, in the earth, is thrust upwards by the natural power of fire, it proceeds to its own appropriate place; and if it meets with any respite or [*]