The gods did not reveal, from the beginning,
All things to us; but in the course of time,
Through seeking we may learn, and know things better
This, as we well may conjecture, resembles the truth.
But as for certain truth, no man has known it,
Nor will he know it; neither of the gods
Nor yet of all things of which I speak.
And even if perchance he were to utter
The perfect truth, he would himself not know it;
For all is but a woven web of guesses.
A translation by Karl Popper of one of his favourite quotations from the pre-socratic philosopher Xenophanes. In The World of Parmenides: Essays on the Presocratic Enlightenment.