But I think he was the only person I have ever known in whom pessimism and optimism were lodged in exactly equal proportions.

Except in the matter of grounded principle, he was as unstable as water.

You could dash his spirits with a single word; you could raise them into the sky again with another one.

You could break his heart with a word of disapproval; you could make him as happy as an angel with a word of approval.

And there was no occasion to put any sense or any vestige of mentality of any kind into these miracles; anything you might say would answer.
He had another conspicuous characteristic, and it was the father of those which I have just spoken of.