Phaedo: On Suffering

I will tell you, he said. Because those who love to learn know that philosophy , upon taking hold of their soul- their soul, which has hitherto been completely bound up all around by and stuck to the physical body, and so forced, as if it were in a prison, to perceive the beings, not by itself through itself, but through that prison in which it is spun round with every kind of ignorance; that philosophy, upon recognizing the terrible nature of that prison as being caused by desire – inasmuch as he who is imprisoned is ever an accomplice in his own imprisonment – the very things I have been just now saying – that those who love to learn know that philosophy, by gently taking hold of their soul, attempts to coax and persuade them to set their soul free, showing them that perception through the eyes is rife with deception, and of deception is also the perception through the ears and the other senses, and so it persuades the soul to begin to withdraw from the senses, except to the extent that it is necessary to use them, and instead to recover the soul back to itself and call it to retrieve its pieces back together, and to trust in nothing other than herself by herself, so that she might be able to intellect by herself through herself each of the beings as they are according to themselves: and that should it perceive something outside of itself in things outside of itself through means outside of it, it should regard that something as untrue, and that it is what is perceived through the senses and seen, while which is true is invisible and is that which she herself sees through intellect. And the soul of one who is truly a philosopher, in believing that one must do nothing to avoid this process of freedom, keeps away as much as she can from pleasures and desires and pains and fears, reckoning that, whenever someone experiences extreme pleasure or fear or pain or desire, they have not suffered as a great an evil as some have been wont to believe, like getting sick or wasting away due to desire, but that the greatest and extreme of all evils, is that they are not able to understand what they are suffering.

Phaedo, 82e -Translation by Anastasia Harris