Leviathan · Chapter
Of Reason and Science explained
Hobbes defines reason as a form of reckoning—adding and subtracting consequences of general names.
What happens
Hobbes defines reason as a form of reckoning—adding and subtracting consequences of general names. He distinguishes between prudence (gained by experience) and science (certain knowledge of consequences), warns against absurdities caused by ambiguous language and metaphors, and argues that true science requires exact definitions and orderly method.
Themes in this chapter
Human Nature and Passions
Hobbes discusses how men often mistake their passions for right reason, leading to contention and sedition.
Justice and Law
The chapter links proper reasoning to the determination of right and wrong in private actions through the addition of laws and facts.
Key passages
“reason is the pace; increase of science, the way; and the benefit of mankind, the end.”
Reason is the method, the growth of knowledge is the path, and human welfare is the ultimate goal.
Hobbes summarizes the purpose and process of rational inquiry.
“metaphors, and senseless and ambiguous words, are like ignes fatui; and reasoning upon them is wandering amongst innumerable absurdities and their end, contention and sedition, or contempt.”
Metaphors and vague words are like misleading lights; reasoning with them leads to absurdities and ultimately to conflict or scorn.
Hobbes warns against the dangers of unclear language in reasoning.