We live together, we act on, and react to, one another; but always and in all circumstances we are by ourselves.  The martyrs go hand in hand into the arena; they are crucified alone.  Embraced, the lovers desperately try to fuse their insulated ecstasies into a single self-transcendence; in vain.  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.  We can pool information about experiences, but never the experiences themselves.  From family to nation, every human group is a society of island universes.