There is a distinction, but no opposition, between theory and practice. Each to a certain extent supposes the other. Theory is dependent on practice; practice must have preceded theory.

An instinct is an agent which performs blindly and ignorantly a work of intelligence and knowledge.

A judgment is the mental act by which one thing is affirmed or denied of another.

Logic is the science of the laws of thought, as thought,--that is of the necessary conditions to which thought considered in itself is a subject.

The pursuit of knowledge is but a course between two ignorances, as human life is itself only a wayfaring from grave to grave.

Truth like a torch, the more 'tis shock, it shines.

In our natural body every part has a necessary sympathy with every other; and all together form, by their harmonious conspiration, a healthy whole.