Since I have a concentration deficit at times, aphorisms are great morsels of easily digestible pieces of wisdom and insight.
I recommend the broad and eclectic collection of aphorisms collected by James Geary. Geary also includes a short bio on the authors of the aphorisms and generally a dozen or more of their best efforts.
The list below caught my eye and mind:
1. The best way to convince a fool that he is wrong is to let him have their own way.
2. Headstone: death's bookmark.
3. A boss: the less he speaks, the more he is heard.
4, What makes old age so sad is not that our joys but our hopes cease.
5. The less we know, the longer our explanations.
6. To read fast is as bad as to eat in a hurry.
7. A precondition for reading good books is not reading bad ones: for life is short.