I think, therefore I am — the foundation of modern philosophy and scientific method.
Why this book matters
The book that gave the world 'I think, therefore I am' — and quietly dismantled a thousand years of intellectual authority.
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Good sense is, of all things among men, the most equally distributed; for every one thinks himself so abundantly provided with it, that those even who are the most difficult to satisfy in everything else, do not usually desire a larger measure of this quality…
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The book that gave the world 'I think, therefore I am' — and quietly dismantled a thousand years of intellectual authority.
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- René Descartes (the Narrator / "I")
- The author-narrator, a former student of philosophy and mathematics who recounts his dissatisfaction with traditional learning and sets out to build knowledge on a new, more certain foundation.
- God (the Perfect Being)
- Referenced early on as the ultimate guarantor of truth; Descartes begins to explore whether God's existence can be established with the same certainty as geometry.
- The Schoolmen / Philosophers of the Schools (the learned)
- The traditional Scholastic thinkers and their logic-based methods, which Descartes contrasts unfavorably with his own emerging method early in the work.
- The Geometers (mathematicians)
- Held up early as a model group whose demonstrations achieve real certainty, inspiring Descartes to imitate their step-by-step reasoning in philosophy.
Glossary
- Cogito ergo sum
- "I think, therefore I am" — the first certain truth Descartes claims to find after doubting everything else, since the act of doubting proves a thinking self exists.
- Clear and distinct
- Descartes's technical standard for certainty: an idea perceived so plainly by the mind that no reasonable doubt about it remains.
- Paralogism
- A flawed or fallacious piece of reasoning, especially one that seems logically valid but leads to a false conclusion.
- Hypotheses (as used by Descartes)
- Explanatory starting assumptions in his scientific treatises (like the Dioptrics and Meteorics) that he presents provisionally, to be justified later by the effects they successfully explain.
- Dioptrics / Meteorics
- Two of Descartes's scientific treatises, on optics and on weather/atmospheric phenomena, published alongside or referenced near the Discourse.
- Art of Lully
- A reference to Ramon Llull's combinatorial logical system, cited by Descartes as an example of clever-sounding but ultimately empty method for discussing unknown things.
- Moral assurance vs. metaphysical certitude
- Descartes's distinction between the practical confidence we have in everyday beliefs (moral assurance) and the absolute, doubt-proof certainty (metaphysical certitude) his method demands.
- Geometrical analysis
- The ancient method of resolving geometric problems by working backward from what is sought to known principles, one of the tools Descartes examined while forming his own method.
- Good sense (bon sens)
- Descartes's term for the innate human capacity for sound judgment, which he argues is equally distributed among all people, differing only in how it is applied.
- Chaos (in Descartes's cosmology)
- The imagined initial disordered state of matter from which Descartes hypothesizes the ordered heavens, stars, and earth could have arisen through natural laws.
Table of contents
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