The writings of this most important of pre-Socratic philosophers is in the form of aphorisms, with many maxim and illustrations of his points, much in the riddling manner of an oracle, which was perhaps why he was known as ‘the dark philosopher’.
The philosopher was famous for the saying, 'You cannot swim twice in the same river', was a born into an aristocratic family, but declined the high position hence due him, cynical after seeing democracy fail and turn into anarchy, and contemptuous of humankind.
He chose the solitude of the sanctuary of Artemis to the life of public affairs. Rather than water, considered the primordial substance by Thales, he believed that fire was the primary cause, transformed first into water, then condensed into earth, and finally returning to fire in a continual cycle.
His belief in constant flux is reflected in the saying quoted above, meaning that nothing remains the same, since all is in constant motion. His ideas about evolution involves fire as the motive force, with heat representing awareness and motion, which were related, as cold., antithetically, symbolizing stillness, or lack of life.
He saw the elements in constant struggle, with life coming about due to a temporary state of balance, which presented the illusion of permanency, though the opposing elements always reverted to struggle and conflict.
Perhaps in regard to his view of perpetual flux and the illusion of a fixed reality, his philosophy resembled that of Hindu philosophy, with its concept of 'maya' (illusion).
Socrates was given a copy of Heraklitos' work, entitled 'On Nature', by Euripides, and Socrates comment upon reading it was that what he had understood was significant, but that what he had failed to understand was equally so, and that 'you must be a very strong swimmer of the spirit not to drown in this book'.
Sayings attributed to Heraklitos :
'War is the father of all things'
'Reality is both one and many'
'The road up and the road down are one and the same'
'All is flux, nothing stays still'