– How Antoine-Léonard Thomas expanded Descartes’ famous argument, and what doubt reveals about the mind, the self and existence

 

I CAME across an interview with Anne Carson, the Nobel Prize-winning poet and writer, in which she discussed the French philosopher René Descartes and his famous declaration, “I think, therefore I am.” Something about the discussion caught my attention, particularly the idea that the familiar phrase may leave out the first step of the inquiry: doubt. Before we arrive at “I think, therefore I am”, might we first have to acknowledge, “I doubt”?

The expanded expression is Dubito, ergo cogito, ergo sum, meaning “I doubt, therefore I think, therefore I am.” Although it is often associated with Descartes, the fuller formulation is credited to Antoine-Léonard Thomas, a French poet and literary critic who wrote an award-winning eulogy for Descartes in 1765. Thomas expressed the reasoning in French: “Puisque je doute, je pense; puisque je pense, j’existe” (“Since I doubt, I think; since I think, I exist”).

This additional step makes the argument more interesting because doubt is where Descartes’ philosophical investigation began.

In his Meditations on First Philosophy, published in 1641, Descartes questioned the reliability of almost everything he believed. Our senses can deceive us; dreams can feel extremely real; and he even imagined a powerful deceiver manipulating his understanding of the world. He wanted to discover whether any belief could survive the most thorough examination imaginable.

Eventually, he encountered something that doubt itself could not eliminate. If he was questioning his existence, then the questioning was happening. If he was being deceived, there had to be an experience of deception. His famous Cogito, ergo sum, “I think, therefore I am”, expressed this discovery. In the Meditations, his formulation is closer to “I am, I exist”, whenever he thinks it.

Descartes was not suggesting that every thought is reliable or that intelligent people possess some special guarantee against foolishness. If thinking alone made us wise, humanity would have solved its problems centuries ago, and several public figures would have to reconsider their careers. His argument was narrower: thinking provides a starting point for recognising existence, even when everything else seems open to question. Yet this starting point does not settle the larger mystery. What exactly is the “I” that thinks? Is it the brain, the mind, the body, the personality we present to others, or something deeper that experiences all of these? Descartes himself argued for a fundamental distinction between mind and body, a position that has generated centuries of debate. The cogito establishes a foothold for inquiry, but it does not independently prove that the mind exists separately from the body.

Psychology adds another dimension to the discussion. William James, the American philosopher and psychologist, described consciousness as a stream rather than a neat procession of isolated thoughts. Our memories, feelings, sensations and ideas flow into one another, creating a changing experience that generally feels continuous.

We recognise ourselves as the same person moving through the day, despite changes in mood, attention and memory. We may wake feeling philosophical, become impatient before breakfast and forget why we entered the kitchen by lunchtime. The person experiencing all of this remains familiar to us, although the contents of the mind are constantly changing. There is also a difference between the self that experiences and the self we examine. One aspect of being conscious involves seeing, hearing, feeling and thinking. Another involves reflecting on our identity, including our memories, relationships, habits, ambitions and personal history. The name we answer to and the story we tell about ourselves help shape our identity, but neither necessarily captures the full complexity of our immediate experience.

Psychologists study part of this reflective ability through metacognition, which means thinking about our own thinking. We question the accuracy of a memory, reconsider a judgement or wonder whether our confidence is justified. This ability helps us identify mistakes and seek better evidence, although we can be confidently wrong or doubt ourselves when our reasoning is sound. Researcher Stephen Fleming and other scientists study how people evaluate their own knowledge and mental performance, including the brain processes involved in these judgements.

Neuroscience brings the physical brain and body into the picture. Neurologist Antonio Damasio challenged the idea that reason operates independently of emotion. In Descartes’ Error, he argued that feelings and bodily signals contribute to decision-making. Our choices emerge from a living system in which emotion, memory, physical condition and reasoning interact.

Think of a moment when you sensed that something was wrong before you could explain why. Perhaps you noticed a change in someone’s expression or an unfamiliar tension in a conversation. Your body may have responded before you consciously identified the details. Such responses can offer useful information, although intuition can also mislead us, which is why reflection and evidence remain important.

Damasio’s work reminds us that the person who declares “I think” is part of a complex biological process. The brain regulates the body, responds to the environment and processes information long before we sit down to analyse our own existence. Still, his account is an influential scientific theory rather than a final verdict on consciousness.

Researchers continue to debate how conscious experience arises and why it feels like something from the inside. Brain activity associated with awareness can be studied, and changes in brain function can affect memory, personality and self-perception. Yet identifying the biological processes involved does not automatically explain the full nature of subjective experience. The brain remains an extraordinary subject of investigation, particularly because it is also the instrument conducting the investigation.

Spiritual traditions approach the question from another direction. Many contemplative practices invite people to observe their thoughts rather than identify automatically with everything the mind produces. A thought appears, occupies our attention and eventually passes. We can then ask who or what is aware of that movement.

This resembles philosophical self-inquiry in its willingness to question familiar assumptions, although spiritual interpretations and scientific explanations operate differently. Descartes sought a secure foundation for knowledge through reason. Contemplative traditions may explore awareness through meditation, observation and reflection. Some interpret that awareness in terms of an enduring spiritual essence; others focus on the experience itself without making claims about an eternal soul.

For me, this is where the conversation becomes especially relevant to everyday life. We spend much energy defending our opinions, explaining our behaviour and protecting the identities we have constructed. Doubting an assumption can feel uncomfortable because it asks us to reconsider something we may have treated as part of ourselves. Yet questioning a belief does not diminish us. It gives us an opportunity to discover whether that belief deserves to remain. Of course, doubt can become excessive. We can question every decision until ordinary life resembles a committee meeting that never reaches a vote. Useful doubt requires curiosity, evidence and the willingness to draw a reasonable conclusion when the facts support one. Its purpose is to sharpen understanding, rather than leave us permanently suspended between possibilities.

Philosophy examines what we can reasonably claim to know. Psychology investigates how we experience ourselves and assess our own thinking. Neuroscience studies the biological processes that support thought, emotion and awareness. Each discipline contributes something valuable, while reminding us that the mystery of the self remains larger than any single explanation.

Perhaps the lasting appeal of Dubito, ergo cogito, ergo sum lies in its invitation to begin with an honest question. Doubt leads us to examine our thoughts; examining our thoughts can deepen our understanding; and deeper understanding can reveal how much remains to be explored.

We may never resolve every question about the nature of existence, but we can learn to approach those questions with greater humility, curiosity and intellectual courage. Sometimes the most useful discovery begins when we stop defending what we think we know long enough to examine how we came to believe it.

 

The Witness Within

 

I questioned every witness that my senses brought to trial,

The world became a labyrinth, each answer frail;

Yet doubt itself stood breathing where my certainties had fled,

A flicker in the darkness, proving thought was not yet dead.

 

Cogito, ergo sum, the mind declared its claim,

But who inhabits thought, and who stands witness to its flame?

A thousand selves have lived in me, each certain of its name,

While time unstitched their portraits and left none quite the same.

 

The thought arrives, the thought departs, like swallows through the air,

The mind constructs a thousand worlds and swears that they are there;

But what remains beneath the words, the memories, the roles,

When silence turns its ancient gaze upon our restless souls?

 

The mystics turn the question round and ask the self to see

Whether the one who watches thought is what it claims to be;

The answer waits beyond the reach of doctrine, creed or art,

Where language loses confidence and inquiry must start.

 

I doubt, and therefore question; I question, and I learn,

Each shattered little assumption gives another page to turn;

For ignorance can fertilize the ground where insight grows,

If we possess the grace to see how little each of us knows.

 

Perhaps the self is deeper than the stories we rehearse,

A question moving through the mind, a witness to the universe;

Or perhaps we seek a permanence no passing thought can prove,

And name the silence something more because we long to know.

 

So let me doubt with discipline, let thought examine me,

Let neither fear nor dogma dictate what I see;

For wisdom may begin the day my proud conclusions part,

And leave an open doorway in the architecture of the heart.

 

Romella Dasratt