We learn particularly from the Timaeus of Plato, that the Egyptians believed the world to be subject to occasional conflagrations and deluges, whereb… - Charles Lyell

Of Dr. Hooker, whom I have often cited in this chapter, Mr. Darwin has spoken in the Introduction to his 'Origin of Species, as one 'who had, for fifteen years, aided him in every possible way, by his large stores of knowledge, and his excellent judgement.' This distinguished botanist published his 'Introductory Essay to the Flora of Australia' in 1859, the year after the memoir on 'Natural Selection' was communicated to the Linnaean Society, and a few months before the appearance of the' Origin of Species.' ...no one was better qualified by observation and reflection to give an authoritative opinion on the question, whether the present vegetation of the globe is or is not in accordance with the theory which Mr. Darwin has proposed. We cannot but feel, therefore, deeply interested when we find him making the following declaration: 'The mutual relations of the plants of each great botanical province, and, in fact, of the world generally, is just such as would have resulted if variation had gone on operating throughout indefinite periods, in the same manner as we see it act in a limited number of centuries, so as gradually to give rise in the course of time, to the most widely divergent forms. ...The element of mutability pervades the whole Vegetable Kingdom; no class, nor order, nor genus of more than a few species claims absolute exemption from it, whilst the grand total of unstable forms, generally assumed to be species, probably exceeds that of the stable.'

The sect of Stoics adopted most fully the system of catastrophes destined at certain intervals to destroy the world. These they taught were of two kinds-the Cataclysm, or destruction by deluge, which sweeps away the whole human race, and annihilates all the animal and vegetable productions of nature; and the Ekpyrosis, or conflagration, which dissolves the globe itself. From the Egyptians also they derived the doctrine of the gradual debasement of man from a state of innocence. Towards the termination of each era the gods could no longer bear with the wickedness of men, and a shock of the elements or a deluge overwhelmed them; after which calamity, Astrea again descended on the earth, to renew the golden age.

When we study history we obtain a more profound insight into human nature by instituting a comparison between the present and former states of society.