Deductive reasoning Deductive reasoning Deductive reasoning, also deductive logic, logical deduction is the process of reasoning from one or more statements (premises) to reach a logically certain conclusion. Deductive reasoning goes in the same direction as that of the conditionals, and links premises with conclusions. If all premises are true, the terms are clear, and the rules of deductive logic are followed, then the conclusion reached is necessarily true. Deductive reasoning (""top-down logic"") contrasts with inductive reasoning (""bottom-up logic"") in the following way; in deductive reasoning, a conclusion is reached reductively by applying general rules which hold over the entirety of a
Logical positivism priori", statements claiming states of facts but known true before experience—by arriving at transcendental idealism, attributing the mind a constructive role in phenomena by arranging sense data into the very experience "space", "time", and "substance". Thus, Kant saved Newton's law of universal gravitation from Hume's problem of induction by finding uniformity of nature to be "a priori" knowledge. Logical positivists rejected Kant's synthethic "a priori", and staked Hume's fork, whereby a statement is either analytic and "a priori" (thus necessary and verifiable logically) or synthetic and "a posteriori" (thus contingent and verifiable empirically). Early, most logical positivists proposed that all