He who loves practice without theory is like the sailor who boards ship without a rudder and compass and never knows where he may cast.
The five senses are the ministers of the soul.
Art lives from constraints and dies from freedom.
Avoid studies of which the result dies with the worker.
Nature never breaks her own laws.
Truth at last cannot be hidden. Dissimulation is of no avail. Dissimulation is to no purpose before so great a judge. Falsehood puts on a mask. Nothing is hidden under the sun.