Book Notes on Ewing (B)

(Originally written September 12, 2006 in Book 8)

Geometry is likewise necessarily a priori. If it were empirical, then we would have to draw figures for every proof and make a very unscientific and hazardous speculation that the single figure drawn can represent all the figures.

The "a priori" in logic

"The laws of logic must be known a priori or not at all" (Pojman, 386).

A syllogism is an important form of a priori knowledge. It consists of three propositions: two are premises, one is the conclusion.

Other cases of the "A priori"

A priori knowledge is most prevalent in mathematics and logic, although it is not limited to these fields.

Philosophers have been divided into two major classes (rationalists and empiricists) based on their stressing of a priori knowledge.

The possibilities of metaphysics is based on a priori knowledge.

A priori knowledge comes from self-evident truths and truth derived by inferences from self-evident principles.

The Linguistic theory of the "A priori" and the denial that "a priori" propositions or inferences can give new knowledge

Empiricists are not in the business of explaining away a priori propositions as merely empirical generalizations. They have adopted the view that a priori cannot tell us anything new about the real world.

They have decided that a prior is simply clarifying language.

Empiricists often admit that there are a priori analytic truths, but deny a priori synthetic truths.

The proposition "there are no synthetic a priori propositions" cannot be verified by experience. Thus, to justify it would prove that there are synthetic a priori propositions./

Many people have denied synthetic a priori knowledge due to the reduction of Euclidean geometry's axioms to analytic propositions. While this may show that the axioms are not synthetic a priori, it does not show that the steps taken after the axioms are not synthetic a priori.

Empiricists play with language to deny synthetic a priori propositions.

"An a priori proposition cannot fully be understood without being seen to be true" (Pojman, 390).

The existence of a priori judgments must be taken as an ultimate fact. We cannot explain their existence any more than we can explain the existence of man's ability to make empirical judgments.

"Human beings certainly cannot explain everything, whether there is ultimately an explanation for it or not" (Pojman, 390).