a. As first truths, or primary data of intelligence, they are, of course, not derived from observation or experience, but are prior and necessary to such experience.
b. They are simple truths, not resolvable into some prior and comprehending truth from which they may be deduced.
c. As simple truths, they do not admit of proof, there being nothing more certain which can be brought in evidence of them.
d. While they do not admit of proof, the denial of them involves us in absurdity.
e. Accordingly, as simple, and as self-evident, they are universally admitted.
Enumeration of some of the Truths usually regarded as primary.—Different writers have included some more, some fewer, of these first principles in their list; while no one has professed, so far as I am aware, to give a complete enumeration of them. Such an enumeration, if it were possible, would be of great service in philosophy. The following have been generally included among primary truths by those who have attempted any specification, viz.; our personal existence, our personal identity, the existence of efficient causes, the existence of the material world, the uniformity of nature; to which would be added, by others, the reliability of memory, and of our natural faculties generally, and personal freedom or power over our own actions and volitions.
Correctness of this Enumeration.—That the truths now specified are in some sense primary, that they are generally admitted and acted upon, among men, without process of reasoning, and that, when stated, they command the universal and instant assent of even the untaught and unreflecting mind, there can be little doubt. Whether, in all cases, however, they come strictly under the rules and criteria now given; whether, for example, our own existence and identity are primary data of consciousness; or whether, on the contrary, they are not inferred from the existence of those thoughts and feelings of which we are directly conscious, as, for example, in the famous argument of Descartes, Cogito, ergo sum, may admit of question.
§ II.—Intuitive Conceptions.
Of the results or operations of the faculty under consideration, we have considered, as yet, only that class which may be designated as primary truths, in distinction from primitive or intuitive conceptions. To this latter class let us now direct our attention.
Proposed consideration of some of the more important.—Without undertaking to give a complete list of our original or intuitive conceptions, there are certain of the more important, which seem to require specific consideration. Such are the ideas of space, time, identity, cause, the beautiful, the right—ideas difficult to define and explain, but, on that account, requiring the more careful investigation. Let us, then, take up these conceptions one by one, and inquire more particularly into their nature.