A world without love would be no world.

If everyone sweeps before his own front door, then the street is clean.

You must either conquer and rule or serve and lose, suffer or triumph, be the anvil or the hammer.

To the man of thought almost nothing is really ridiculous.

Be always resolute with the present hour. Every moment is of infinite value.

The destiny of any nation at any given time depends on the opinion of its young people, those under twenty-five.

Hypotheses are only the pieces of scaffolding which are erected round a building during the course of construction, and which are taken away as soon as the edifice is completed.