Metaphysics is universal and is exclusively concerned with primary substance. ... And here we will have the science to study that which is, both in its essence and in the properties which it has.

Metaphysics involves intuitive knowledge of unprovable starting-points concepts and truth and demonstrative knowledge of what follows from them.

Of the irrational part of the soul again one division appears to be common to all living things, and of a vegetative nature.

The greatest injustices proceed from those who pursue excess, not by those who are driven by necessity.

The man who confers a favour would rather not be repaid in the same coin.

It is the mark of an educated mind to be able to entertain a thought without accepting it.

Modesty is hardly to be described as a virtue. It is a feeling rather than a disposition. It is a kind of fear of falling into disrepute.