We live together, we act on, and react to, one another; but always and in all circumstances we are by ourselves. [...] By its very nature every embodied spirit is doomed to suffer and enjoy in solitude. Sensations, feelings, insights, fancies - all these are private and, except through symbols and at second hand, incommunicable.
A physical shortcoming could produce a kind of mental excess. The process, it seemed, was reversible. Mental excess could produce, for its own purposes, the voluntary blindness and deafness of deliberate solitude, the artificial impotence of asceticism.