Just as water, sealed within a hermetic conduit, is often pushed upwards, vertically, by the rising pressure for lack of space for expansion (and this despite its natural movement that pushes it down), so too the human intellect, strictly channeled from all directions by temperance, will be as though lifted up to the desire for superior goods by its natural tendency to move, lacking any exit or place of diversion; for the being in constant movement, having received such a nature from its Creator, can never be stabilized; and if it is prevented from employing its movement in the direction of vain things, it has no other recourse but to go straight to reality.
~St Gregory of Nyssa
Prayerful Life 