Unless we love and are loved, each of us is alone, each of us is deeply lonely.

There are places and moments in which one is so completely alone that one sees the world entire.

Every man must do two things alone he must do his own believing and his own dying.

I don't want to be alone, I want to be left alone.

I love to be alone. I never found the companion that was so companionable as solitude.

Associate with men of good quality if you esteem your own reputation for it is better to be alone than in bad company.

You cannot be lonely if you like the person you're alone with.

Look at the sky. We are not alone. The whole universe is friendly to us and conspires only to give the best to those who dream and work.

All of our unhappiness comes from our inability to be alone.

If it's true that our species is alone in the universe, then I'd have to say the universe aimed rather low and settled for very little.