There is convincing evidence that the search for solitude is not a luxury but a biological need. Just as humans posses a herding instinct that keeps us close to others most of the time, we also have a conflicting drive to seek out solitude. If the distance between ourselves and others becomes too great, we experience isolation and alienation, yet if the proximity to others becomes too close, we feel smothered and trapped.
We are all prone to the malady of the introvert who, with the manifold spectacle of the world spread out before him, turns away and gazes only upon the emptiness within. But let us not imagine there is anything grand about the introvert's unhappiness.
Alone, even doing nothing, you do not waste your time. You do, almost always, in company. No encounter with yourself can be altogether sterile: Something necessarily emerges, even if only the hope of some day meeting yourself again.