1934–1996
Carl Sagan
Uses wonder and skepticism to place humanity in a vast, fragile cosmic context.
Astronomy · Ethics · Public Reason
The living archive
Schools of thought
Browse the traditions, disciplines, and recurring questions that organize the Thought library.
Featured School
Astronomy
Enter a curated collection of thinkers, works, and questions that continue to shape how we understand the world.
2 thinkers1 thoughts
Featuring Galileo GalileiExplore the collection →Philosophy
11 thinkers · 1 thoughts
African American Thought
A curated path through the thinkers, works, and enduring questions gathered in African American Thought.
4 thinkers · 1 thoughts
African Diaspora Thought
A curated path through the thinkers, works, and enduring questions gathered in African Diaspora Thought.
18 thinkers · 3 thoughts
African Thought
A curated path through the thinkers, works, and enduring questions gathered in African Thought.
1 thinkers · 0 thoughts
Analytic Philosophy
A curated path through the thinkers, works, and enduring questions gathered in Analytic Philosophy.
1 thinkers · 0 thoughts
Anarchism
A curated path through the thinkers, works, and enduring questions gathered in Anarchism.
13 thinkers · 5 thoughts
Ancient Philosophy
A curated path through the thinkers, works, and enduring questions gathered in Ancient Philosophy.
4 thinkers · 0 thoughts
Anti-Caste Thought
A curated path through the thinkers, works, and enduring questions gathered in Anti-Caste Thought.
11 thinkers · 1 thoughts
Anti-Colonial Thought
A curated path through the thinkers, works, and enduring questions gathered in Anti-Colonial Thought.
1 thinkers · 0 thoughts
Civic Thought
A curated path through the thinkers, works, and enduring questions gathered in Civic Thought.
2 thinkers · 0 thoughts
Comparative Philosophy
A curated path through the thinkers, works, and enduring questions gathered in Comparative Philosophy.
1 thinkers · 0 thoughts
Complexity
A curated path through the thinkers, works, and enduring questions gathered in Complexity.
1 thinkers · 0 thoughts
Contemporary Philosophy
A curated path through the thinkers, works, and enduring questions gathered in Contemporary Philosophy.
2 thinkers · 0 thoughts
Continental Philosophy
A curated path through the thinkers, works, and enduring questions gathered in Continental Philosophy.
1 thinkers · 1 thoughts
Critical Thinking
A curated path through the thinkers, works, and enduring questions gathered in Critical Thinking.
4 thinkers · 1 thoughts
Cultural Studies
A curated path through the thinkers, works, and enduring questions gathered in Cultural Studies.
1 thinkers · 0 thoughts
Cultural Theory
A curated path through the thinkers, works, and enduring questions gathered in Cultural Theory.
2 thinkers · 0 thoughts
Development Thought
A curated path through the thinkers, works, and enduring questions gathered in Development Thought.
12 thinkers · 2 thoughts
Eastern Philosophy
A curated path through the thinkers, works, and enduring questions gathered in Eastern Philosophy.
10 thinkers · 3 thoughts
Ecology
A curated path through the thinkers, works, and enduring questions gathered in Ecology.
18 thinkers · 3 thoughts
Education
A curated path through the thinkers, works, and enduring questions gathered in Education.
1 thinkers · 0 thoughts
Embodiment
A curated path through the thinkers, works, and enduring questions gathered in Embodiment.
2 thinkers · 0 thoughts
Empiricism
A curated path through the thinkers, works, and enduring questions gathered in Empiricism.
1 thinkers · 0 thoughts
Enlightenment
A curated path through the thinkers, works, and enduring questions gathered in Enlightenment.
1 thinkers · 0 thoughts
Environmental Thought
A curated path through the thinkers, works, and enduring questions gathered in Environmental Thought.
73 thinkers · 8 thoughts
Ethics
A curated path through the thinkers, works, and enduring questions gathered in Ethics.
7 thinkers · 2 thoughts
Existentialism
A curated path through the thinkers, works, and enduring questions gathered in Existentialism.
28 thinkers · 6 thoughts
Feminist Thought
A curated path through the thinkers, works, and enduring questions gathered in Feminist Thought.
1 thinkers · 0 thoughts
Game Theory
A curated path through the thinkers, works, and enduring questions gathered in Game Theory.
1 thinkers · 0 thoughts
Global Studies
A curated path through the thinkers, works, and enduring questions gathered in Global Studies.
2 thinkers · 0 thoughts
Hermeneutics
A curated path through the thinkers, works, and enduring questions gathered in Hermeneutics.
13 thinkers · 0 thoughts
Indian Thought
A curated path through the thinkers, works, and enduring questions gathered in Indian Thought.
7 thinkers · 1 thoughts
Indigenous Thought
A curated path through the thinkers, works, and enduring questions gathered in Indigenous Thought.
1 thinkers · 0 thoughts
Information Theory
A curated path through the thinkers, works, and enduring questions gathered in Information Theory.
1 thinkers · 0 thoughts
Intuition
A curated path through the thinkers, works, and enduring questions gathered in Intuition.
3 thinkers · 0 thoughts
Justice
A curated path through the thinkers, works, and enduring questions gathered in Justice.
1 thinkers · 0 thoughts
Labor Thought
A curated path through the thinkers, works, and enduring questions gathered in Labor Thought.
15 thinkers · 2 thoughts
Language & Meaning
A curated path through the thinkers, works, and enduring questions gathered in Language & Meaning.
4 thinkers · 0 thoughts
Latin American Thought
A curated path through the thinkers, works, and enduring questions gathered in Latin American Thought.
4 thinkers · 0 thoughts
Law
A curated path through the thinkers, works, and enduring questions gathered in Law.
2 thinkers · 0 thoughts
Leadership
A curated path through the thinkers, works, and enduring questions gathered in Leadership.
4 thinkers · 1 thoughts
Liberal Thought
A curated path through the thinkers, works, and enduring questions gathered in Liberal Thought.
1 thinkers · 0 thoughts
Libertarian Thought
A curated path through the thinkers, works, and enduring questions gathered in Libertarian Thought.
4 thinkers · 1 thoughts
Literary Theory
A curated path through the thinkers, works, and enduring questions gathered in Literary Theory.
4 thinkers · 2 thoughts
Medieval Philosophy
A curated path through the thinkers, works, and enduring questions gathered in Medieval Philosophy.
7 thinkers · 2 thoughts
Modern Philosophy
A curated path through the thinkers, works, and enduring questions gathered in Modern Philosophy.
7 thinkers · 3 thoughts
Modern Thought
A curated path through the thinkers, works, and enduring questions gathered in Modern Thought.
3 thinkers · 3 thoughts
Natural Philosophy
A curated path through the thinkers, works, and enduring questions gathered in Natural Philosophy.
2 thinkers · 0 thoughts
Organizational Thought
A curated path through the thinkers, works, and enduring questions gathered in Organizational Thought.
4 thinkers · 0 thoughts
Pan-Africanism
A curated path through the thinkers, works, and enduring questions gathered in Pan-Africanism.
1 thinkers · 0 thoughts
Peace Studies
A curated path through the thinkers, works, and enduring questions gathered in Peace Studies.
4 thinkers · 0 thoughts
Phenomenology
A curated path through the thinkers, works, and enduring questions gathered in Phenomenology.
2 thinkers · 0 thoughts
Philosophy
A curated path through the thinkers, works, and enduring questions gathered in Philosophy.
4 thinkers · 2 thoughts
Poetry
A curated path through the thinkers, works, and enduring questions gathered in Poetry.
13 thinkers · 3 thoughts
Postcolonial Thought
A curated path through the thinkers, works, and enduring questions gathered in Postcolonial Thought.
2 thinkers · 2 thoughts
Poststructuralism
A curated path through the thinkers, works, and enduring questions gathered in Poststructuralism.
2 thinkers · 0 thoughts
Pragmatism
A curated path through the thinkers, works, and enduring questions gathered in Pragmatism.
1 thinkers · 0 thoughts
Probability
A curated path through the thinkers, works, and enduring questions gathered in Probability.
5 thinkers · 1 thoughts
Public Policy
A curated path through the thinkers, works, and enduring questions gathered in Public Policy.
1 thinkers · 0 thoughts
Public Reason
A curated path through the thinkers, works, and enduring questions gathered in Public Reason.
6 thinkers · 3 thoughts
Rationalism
A curated path through the thinkers, works, and enduring questions gathered in Rationalism.
1 thinkers · 0 thoughts
Research Methodology
A curated path through the thinkers, works, and enduring questions gathered in Research Methodology.
1 thinkers · 1 thoughts
Statistics
A curated path through the thinkers, works, and enduring questions gathered in Statistics.
1 thinkers · 0 thoughts
Symbolism
A curated path through the thinkers, works, and enduring questions gathered in Symbolism.
2 thinkers · 0 thoughts
Urbanism
A curated path through the thinkers, works, and enduring questions gathered in Urbanism.
1 thinkers · 0 thoughts
Utilitarianism
A curated path through the thinkers, works, and enduring questions gathered in Utilitarianism.
1 thinkers · 0 thoughts
Virtue Ethics
A curated path through the thinkers, works, and enduring questions gathered in Virtue Ethics.
1 thinkers · 0 thoughts
Visual Thought
A curated path through the thinkers, works, and enduring questions gathered in Visual Thought.
33 thinkers · 11 thoughts
Western Philosophy
A curated path through the thinkers, works, and enduring questions gathered in Western Philosophy.
Science
2 thinkers · 1 thoughts
Astronomy
A curated path through the thinkers, works, and enduring questions gathered in Astronomy.
2 thinkers · 1 thoughts
Biology
A curated path through the thinkers, works, and enduring questions gathered in Biology.
8 thinkers · 2 thoughts
Computing
A curated path through the thinkers, works, and enduring questions gathered in Computing.
12 thinkers · 4 thoughts
Logic
A curated path through the thinkers, works, and enduring questions gathered in Logic.
24 thinkers · 6 thoughts
Mathematics
A curated path through the thinkers, works, and enduring questions gathered in Mathematics.
22 thinkers · 6 thoughts
Metaphysics
A curated path through the thinkers, works, and enduring questions gathered in Metaphysics.
4 thinkers · 1 thoughts
Philosophy of Science
A curated path through the thinkers, works, and enduring questions gathered in Philosophy of Science.
12 thinkers · 5 thoughts
Physics
A curated path through the thinkers, works, and enduring questions gathered in Physics.
33 thinkers · 11 thoughts
Science
A curated path through the thinkers, works, and enduring questions gathered in Science.
1 thinkers · 0 thoughts
Technology
A curated path through the thinkers, works, and enduring questions gathered in Technology.
8 thinkers · 1 thoughts
Technology & Society
A curated path through the thinkers, works, and enduring questions gathered in Technology & Society.
Psychology & Society
2 thinkers · 1 thoughts
Psychoanalysis
A curated path through the thinkers, works, and enduring questions gathered in Psychoanalysis.
17 thinkers · 3 thoughts
Psychology
A curated path through the thinkers, works, and enduring questions gathered in Psychology.
1 thinkers · 0 thoughts
Social Reform
A curated path through the thinkers, works, and enduring questions gathered in Social Reform.
35 thinkers · 8 thoughts
Social Theory
A curated path through the thinkers, works, and enduring questions gathered in Social Theory.
1 thinkers · 0 thoughts
Sociology
A curated path through the thinkers, works, and enduring questions gathered in Sociology.
Religion & Mysticism
9 thinkers · 3 thoughts
Islamic Philosophy
A curated path through the thinkers, works, and enduring questions gathered in Islamic Philosophy.
5 thinkers · 1 thoughts
Islamic Thought
A curated path through the thinkers, works, and enduring questions gathered in Islamic Thought.
7 thinkers · 1 thoughts
Jewish Thought
A curated path through the thinkers, works, and enduring questions gathered in Jewish Thought.
40 thinkers · 6 thoughts
Religion & Mysticism
A curated path through the thinkers, works, and enduring questions gathered in Religion & Mysticism.
Culture & Strategy
4 thinkers · 1 thoughts
Anti-Apartheid Thought
A curated path through the thinkers, works, and enduring questions gathered in Anti-Apartheid Thought.
17 thinkers · 4 thoughts
Economics
A curated path through the thinkers, works, and enduring questions gathered in Economics.
4 thinkers · 0 thoughts
History
A curated path through the thinkers, works, and enduring questions gathered in History.
1 thinkers · 0 thoughts
History of Ideas
A curated path through the thinkers, works, and enduring questions gathered in History of Ideas.
14 thinkers · 2 thoughts
Literature
A curated path through the thinkers, works, and enduring questions gathered in Literature.
96 thinkers · 17 thoughts
Political Philosophy
A curated path through the thinkers, works, and enduring questions gathered in Political Philosophy.
2 thinkers · 1 thoughts
Strategy
A curated path through the thinkers, works, and enduring questions gathered in Strategy.
Popular Thinkers
1564–1642
Galileo Galilei
Champions observation, experiment, mathematics, and intellectual courage in understanding motion and the cosmos.
Astronomy · Natural Philosophy · Physics
Popular Thoughts
Essay
The Nature of Truth: A Galileo Perspective on Knowledge and Belief
The Nature of Truth: A Galileo Perspective on Knowledge and Belief In our relentless pursuit of understanding, we find ourselves often at the crossroads…
Read Thought“The book of nature is written in mathematical language.”