Intuition and concepts constitute... the elements of all our knowledge, so that neither concepts without an intuition in some way corresponding to them, nor intuition without concepts, can yield knowledge.
Let no young man choosing the law for a calling for a moment yield to the popular belief -- resolve to be honest at all events; and if in your own judgment you cannot be an honest lawyer, resolve to be honest without being a lawyer.
If thou wishest to put an end to love, attend to business (love yields to employment); then thou wilt be safe.
[Lat., Qui finem quaeris amoris,
(Cedit amor rebus) res age; tutus eris.]
When love beckons to you, follow him, Though his ways are hard and steep. And when his wings enfold you yield to him, Though the sword hidden among his pinions may wound you.
Dance music ... stirs some barbaric instinct - lulled asleep in our sober lives - you forget centuries of civilization in a second, & yield to that strange passion which sends you madly whirling round the room.
However we select from nature a complex [of phenomena] using the criterion of simplicity, in no case will its theoretical treatment turn out to be forever appropriate (sufficient).... I do not doubt that the day will come when [general relativity], too, will have to yield to another one, for reasons which at present we do not yet surmise. I believe that this process of deepening theory has no limits.