Along similar (brooding) lines...

It seems that when one knows too much and understands too well (of human frailties maybe), somberness is the result- as reflected in G Babai's and G Pinni's recent posts. Came across this quote from Byron yesterday, which seems to say much the same:

Sorrow is knowledge; they who know the most

Must mourn the deepest o'er the fatal truth,

The Tree of Knowledge is not that of Life.

But then, I would also counter that viewpoint with this 2-liner from Ogden Nash:

When I consider how my life is spent,

I hardly ever repent.