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An Enquiry Concerning Human Understanding · Chapter

Of the Reason of Animals explained

Hume extends his analysis of experimental reasoning to animals, arguing that they, like humans, learn from experience and infer effects from causes through custom and habit, not through rational argument.

What happens

Hume extends his analysis of experimental reasoning to animals, arguing that they, like humans, learn from experience and infer effects from causes through custom and habit, not through rational argument. This analogy confirms that custom is the universal guide of life, and that reasoning in animals is a species of instinct.

Themes in this chapter

  • Custom and Habit as Guides

    Hume argues that animals, like humans, are guided by custom and habit in inferring effects from causes, not by reasoning.

  • Human Nature and Uniformity

    The analogy between human and animal reasoning supports the uniformity of nature and the shared principles of understanding across species.

Characters to notice

  • Narrator

    The narrator presents the argument that animals reason by analogy and custom, not by rational deduction.

Key passages

  • All our reasonings concerning matter of fact are founded on a species of Analogy, which leads us to expect from any cause the same events, which we have observed to result from similar causes.

    All our factual reasoning is based on analogy, expecting similar causes to produce similar effects as observed in the past.

    Hume introduces analogy as the foundation of empirical reasoning.

  • It is custom alone, which engages animals, from every object, that strikes their senses, to infer its usual attendant, and carries their imagination, from the appearance of the one, to conceive the other, in that particular manner, which we denominate belief.

    Only custom leads animals to infer the usual consequence of an object they perceive, forming what we call belief.

    Hume asserts that custom, not reason, is the basis of belief in animals.

An Enquiry Concerning Human Understanding — Of the Reason of Animals Explained