Whatever is the object of a saint's hope is the subject of his prayer.
Mountains cannot be surmounted except by winding paths.
That which thy fathers have bequeathed to thee, earn it anew if thou wouldst possess it.
The use of a thing is only a part of its significance. To know anything thoroughly, to have the full command of it in all its appliances, we must study it on its own account, independently of any special application.
The errors of the observer come from the qualities of the human mind.
The philosophers must station themselves in the middle.