关键词: 演绎推理, 归纳推理, 简化式推理

Abstract: This paper aims to make a fairly thorough study about Sir. Harold Jeffreys′ philosophy of statistics, it is done by illustrating of and commenting on his systematic investigation into certain modern logic concepts, including deductive reasoning, inductive reasoning and reductive reasoning, so as to help us perceive how his statistical thoughts were formed and what the features were in his papers, books etc. It also helps us see why his thoughts can exercise a significant impact on modern statistics and other related disciplines of science.

Key words: Deductive Reasoning, Inductive Reasoning, Reductive Reasoning