PANTHEON
ExploreBuild My Library
© 2026 Pantheon — an atlas of the ideas that shaped how we think.
book1843

A System of Logic

Disciplines:
logic
philosophy/analytic philosophy
philosophy of science/scientific method

Summary

Mill's A System of Logic (1843) is the foundational work of empiricist logic and philosophy of science, defending inductive reasoning as the basis of all knowledge.

Core Contribution

Mill defends a thoroughly empiricist epistemology: even logical and mathematical truths are inductive generalizations from experience; his five methods of inductive inference (agreement, difference, joint method, residues, concomitant variation) became standard tools of scientific methodology.

Key Spikes & Highlights

  • All knowledge from experience (even mathematical truths are inductive — 2+2=4 is a generalization from experience, not a priori)
  • Five methods of induction (agreement, difference, joint method, residues, concomitant variation — the toolkit of empirical causal reasoning)
  • Liberty of thought (the logic's methodology prefigures On Liberty: free inquiry is necessary because we can always be wrong)
  • Ethology (proposed a science of character formation that would explain and predict human behavior scientifically)

Historical Influences

John Stuart Mill

Intellectual Lineage

British empiricism Baconian inductionScientific naturalism

Allied Works

On Liberty Utilitarianism The Subjection of Women

Contemporaries & Peers

On Liberty Utilitarianism The Subjection of Women

Minds Influenced

No recorded minds influenced.

Intellectual Posterity

Mill's methods of inductionEmpiricist philosophy of scienceNaturalistic epistemology

Discussing

A System of Logic

Ask anything about A System of Logic — their ideas, influences, contradictions, legacy.

Sign in to start a conversation.