Preya is what is pleasant now, though in the long run it leads to insecurity and distress. Shreya is what is permanently beneficial, though it sometimes seems unpleasant at first. We are so poorly educated in the art of living that we prefer temporary satisfaction, even though it may lead to permanent loss, to the adventure of bearing a temporary displeasure that leads to permanent fulfillment.
We have to make this choice between preya and shreya every day.
~ Like a Thousand Suns by Eknath Easwaran