Although nature commences with reason and ends in experience it is necessary for us to do the opposite, that is to commence with experience and from this to proceed to investigate the reason.

Man's external form, marvellously constructed, is not much as compared with the divine soul that dwells inside that structure.

There is no result in nature without a cause; understand the cause and you will have no need of the experiment.

He who does not oppose evil......commands it to be done.

Constancy does not begin, but is that which perseveres.

The mind that engages in subjects of too great variety becomes confused and weakened.

It is ordained that to the ambitious, who derive no satisfaction from the gifts of life and the beauty of the world, life shall be a cause of suffering, and they shall possess neither the profit nor the beauty of the world.