Thinker Library

A journey through 2,300 years

A lineage of emotion across thirteen philosophers

From Plato's chariot to Spinoza's conatus, James's bodily account, and Nussbaum's theory of evaluation, follow the eras into the depth of their thought.

The timeline always includes all thirteen thinkers, regardless of the filter above.

1. Plato

   4th century BCE · Ancient · Discovering the mind

   Republic · Phaedrus

   Three minds struggling within me

   Plato did not regard emotion as an evil that must simply be eliminated. If reason is the charioteer, spirit—pride and courage—is the responsive white horse, while appetite—the instinct for pleasure—is the unruly dark horse. As the driver reins in the dark horse and works with the white horse to move the chariot forward, emotion becomes a powerful engine that can lift life toward love and beauty.

   When the temptation of noodles challenges your diet

   Explore Plato

2. Aristotle

   4th century BCE · Ancient · Discovering the mind

   Rhetoric, Book II

   When my judgment changes, my feelings can change too

   Aristotle offered the first detailed, item-by-item analysis of emotion in Western history. In his account of anger, what hurts is not merely a loss but the humiliation of feeling that someone has looked down on us and treated us as insignificant. Emotion is not simply reason's enemy: it is an honest compass revealing how we evaluate the world.

   Why does a friend's success sometimes sting?

   Explore Aristotle

3. The Stoics

   From the 3rd century BCE · Ancient · Discovering the mind

   Chrysippus · Seneca, On Anger

   Three seconds of space when anger boils over

   When someone steps on your foot, the immediate flinch is an involuntary bodily reflex. But spending days fuming, ‘They looked down on me and did it deliberately!’ involves an interpretation added by the mind. The Stoic teaching holds that revising this judgment can let anger melt like snow. This tradition is an important philosophical precursor of modern cognitive behavioral therapy (CBT).

   When unfair treatment keeps you awake

   Explore The Stoics

4. Augustine

   4th–5th centuries · Medieval & early modern · Passion and reason

   The City of God

   The courage to hurt when hurt is called for

   Augustine strongly challenged the demand he associated with Stoicism to eliminate emotion completely, dismissing it as wordplay. Grieving when someone we love dies and feeling anger at injustice can be deeply human, beautiful responses. What matters is not erasing emotion, but loving what is genuinely precious in the right way.

   When holding back sadness leaves a wound inside

   Explore Augustine

5. Thomas Aquinas

   13th century · Medieval & early modern · Passion and reason

   Summa Theologiae, I–II

   Eleven emotional directions within us

   Aquinas, one of the great minds of the Middle Ages, arranged the passions into eleven kinds. We need not only the attraction that draws us toward a good—love, desire, and joy—but also the courage, hope, and fighting spirit of the irascible passions. These arise when a great obstacle stands before us and help us make our way through a difficult world.

   When a towering obstacle makes you want to give up

   Explore Thomas Aquinas

6. René Descartes

   1649 · Medieval & early modern · Passion and reason

   The Passions of the Soul

   The quiet conversation between brain and body

   Descartes held that emotion is not merely an imagining in the head: it begins in exchanges involving the body, brain, and nervous system. We cannot immediately stop a racing heart by willpower alone, but his account suggests that good habits, breathing, and shifts of thought can help us learn to guide the passions skillfully.

   When your heart drops and your hands tremble

   Explore René Descartes

7. Thomas Hobbes

   1651 · Medieval & early modern · Passion and reason

   Leviathan, Chapter 6

   Emotion is the engine that moves the body

   For Hobbes, a human being resembles a living, moving machine. Emotion is not a motionless state of mind, but a motor of action that continually pushes us forward in the effort to survive. Pride that resists falling behind others, together with fear that seeks escape from danger, ultimately helped give rise to civil society and order.

   When worry about the future keeps you awake

   Explore Thomas Hobbes

8. Baruch Spinoza

   1677 · Medieval & early modern · Passion and reason

   Ethics, Part III

   A formula for the joy that replenishes life

   Spinoza did not treat emotion as sinful: he studied it with the objectivity one might bring to weather or geometry. We feel joy when our vitality and sense of ourselves expand, and sadness when they diminish. Calmly understanding the causes of our anger opens a way beyond being a passive victim of emotion toward greater authorship of our lives.

   When self-esteem is low and energy has drained away

   Explore Baruch Spinoza

9. David Hume

   1739 · Medieval & early modern · Passion and reason

   A Treatise of Human Nature, Book II

   The head gives directions; the heart turns the wheel

   Hume's declaration that reason is, and ought to be, the slave of the passions provocatively challenges the idea that reason alone can explain every motive for action. It connects with contemporary inquiry into emotion and decision-making, but we cannot claim that modern neuroscience has simply proved his entire philosophy. Hume emphasized that moral judgment involves not only logic but sympathy: responsiveness to another person's pleasure and pain.

   When you understand what to do but your heart will not move

   Explore David Hume

10. Charles Darwin

    1872 · Modern · Body and mind

    The Expression of the Emotions in Man and Animals

    A survival alarm shaped across millions of years

    Why do our eyes widen in surprise, and why does the nose wrinkle at rotten food? Widened eyes can take in a broader field of danger, while recoiling from a smell can help keep harmful fumes from our lungs. Emotional expressions are not merely displays of mood: in this evolutionary picture, they carry traces of techniques for surviving a demanding natural world.

    When a face seems to tell you what someone feels without words

    Explore Charles Darwin

11. William James

    1884 · Modern · Body and mind

    What Is an Emotion?

    We do not weep because we are sad; we feel sad because we weep

    Common sense gives the sequence: see a bear, feel afraid, then run. James reverses this familiar order, arguing that fear is constituted by feeling bodily changes, such as a pounding heart and trembling, that arise after perceiving danger. His account offers insight into how changes in body and action can influence mood. It does not mean that a single change of posture can resolve all depression or anxiety.

    When your heart pounds just before a presentation

    Explore William James

12. Jean-Paul Sartre

    1939 · Modern · Body and mind

    Sketch for a Theory of the Emotions

    The mind's magic show when we want to escape

    Like the fox in Aesop's fable who cannot reach the grapes and turns away saying they are sour anyway, Sartre attends to the way emotion magically transforms the meaning of the world when practical action is blocked. This should not be reduced to an intentional choice that we consciously deliberate over at every moment. Emotion is a way in which the whole body and consciousness live a situation, allowing us to reflect on its meaning and responsibility together.

    When difficult situations lead you to sleep or withdraw in a sulk

    Explore Jean-Paul Sartre

13. Martha Nussbaum

    From 2001 · Modern · Body and mind

    Upheavals of Thought

    The soul's wisdom about what is precious to us

    Tears at parting from someone can be the soul's recognition of how precious that person has been in our life. Grief and compassion are not simply weak defects: they are intelligent capacities revealing that we are connected to others and live together with them. Respecting emotion helps us build a more caring society.

    When fear of being hurt makes you want to close your heart

    Explore Martha Nussbaum