once you have tasted the taste of sky, you will forever look up

It is no small benefit on finding oneself in bed in the dark to go over again in the imagination the main lines of the forms previously studied, or other noteworthy things conceived by ingenious speculation.

Poor is the pupil who does not surpass his master.

Vitality and beauty are gifts of Nature for those who live according to its laws.

Do not reveal, if liberty is precious to you; my face is the prison of love.

If you throw a stone in a pond... the waves which strike against the shores are thrown back towards the spot where the stone struck; and on meeting other waves they never intercept each other's course... In a small pond one and the same stroke gives birth to many motions of advance and recoil.

Nature never breaks her own laws.