Mistakes are made on two counts: an argument is either based on error or incorrectly developed.

As mariners are guided into port by the shining of a star, so Christians are guided to heaven by Mary.

Far graver is it to corrupt the faith that is the life of the soul than to counterfeit the money that sustains temporal life.

It is not theft, properly speaking, to take secretly and use another's property in a case of extreme need: because that which he takes for the support of his life becomes his own property by reason of that need

For it is necessary in every practical science to proceed in a composite (i.e. deductive) manner. On the contrary in speculative science, it is necessary to proceed in an analytical manner by breaking down the complex into elementary principles.

A scrap of knowledge about sublime things is worth more than any amount about trivialities.

Pray thee, spare, thyself at times: for it becomes a wise man sometimes to relax the high pressure of his attention to work.