Knight’s Back Of The Envelope Philosophy: The Whole Of Epistemology In 400 Words

Make any statement about reality and it will be incomplete in some way. If it is a statement that you can prove with logic or mathematics then it falls short of describing anything conclusive about any reality outside of mathematics or logic; if it is a statement about physical reality then it falls short of anything that can be conclusively proven to apply in all cases (in the black swan sense); if it is a statement of fact then it cannot be established by logic or by reason prior to initial experience; if it is a logical proposition then its subject/predicate content must be verified outside of the proposition; if it is an allusion to an inner concept then it is not knowledge (justified true belief) of the perceivable world; if it is an allusion to an inner perception of outside reality then it escapes your certainty; and if it is a statement about a metaphysical interpretation then in its proprietary form it is entirely subjective.

Everything is derived from experience (this is the basis of Hume’s fork – everything is classified as either Relations of ideas and Matters of fact), but in distinct ways: a priori is knowable without having to consult experience, except initially to understand the terms (“all bachelors are male”); a posteriori is only knowable by consulting experience (“London has a higher population than Birmingham”); analytic statements (A is A) are true by virtue of the meaning of the terms, synthetic statements (A is B) are true by virtue of meanings in relation to facts; physical statements are in relation to the material world (“the chair has four legs”), metaphysical statements are subjective ideas formed as a result of relation to the objective world (“Love and grace triumphs justice and revenge”); and necessity and contingency are related to whether or not a statement is conditioned by how the world happens to be. 

Relations of ideas and Matters of fact describe everything, including all the notions like a priori and a posteriori, necessity and contingency, the physical and the metaphysical and the analytic and synthetic distinctions – they are part of our matters of fact derived through experience, and our relations of ideas that result from that experience.

 

Every possible distinct description of experience is covered above, because everything is either a fact (an impression) derived from experience, or a relation of ideas based on those impressions from experience.