The evolutionary advantage of doubt: how scepticism fuels scientific and ethical progress

David Falls
5 days ago
7 min read

By David Falls

In this article, David explores how scepticism has driven humanity’s greatest advances in science, ethics and understanding. From Galileo’s defiance before the Inquisition to the moral reasoning of modern secular societies, he traces the evolution of enquiry itself: how doubt became one of our species’ most powerful survival instincts and an effective antidote to dogma in every age.

After a 33-year career with Microsoft, David now writes about the ethical and philosophical forces shaping our understanding of consciousness, identity and progress. His work explores where technology, science and culture meet. He holds a BSc from the New York Institute of Technology.

In 1633, Galileo Galilei stood before the Inquisition, accused of heresy for suggesting that Earth was not the centre of the universe. Forced to recant, he whispered, 'And yet, it moves.' His defiance was not blanket disbelief but a focused challenge to a flawed idea. Galileo’s doubt was disciplined – directed at error, not at truth itself. That precision raises a question that still matters: When does scepticism serve progress, and when does it hinder it?

While belief in gods has often been seen as fundamental to civilisation, providing moral frameworks, social cohesion, and existential meaning, critical enquiry has played an equally significant role in shaping human advancement. It is not indiscriminate doubt but reasoned analysis, the kind that questions flawed assumptions, that has fuelled scientific discovery, intellectual freedom, and ethical progress.

Galileo facing the Roman Inquisition (1857) by Cristiano Banti. Image source: Wikimedia Commons. Public Domain.

The evolution of enquiry

The instinct to question is older than science itself. Long before telescopes and theories, early humans learned to doubt what didn’t work. When rituals failed to bring rain, those who experimented – digging channels, tracking seasons – survived. Applied wisely, scepticism became one of humanity’s earliest evolutionary advantages.

A tribe that relied solely on ritual to ensure a successful hunt might struggle, while another that honed its techniques through observation and trial-and-error would thrive. Over generations, natural selection favoured those who sought evidence-based solutions rather than unquestioningly accepting supernatural claims.

Over time, that survival instinct evolved into a habit of mind. The same curiosity that once tested hunting rituals began to question cosmologies, hierarchies and moral codes. What began as a practical advantage became a philosophical one; the courage to question authority itself.

The courage to question

As human understanding matured, that same instinct to test assumptions took aim at the heavens. Galileo’s challenge to geocentrism showed that evidence, not authority, must decide truth. His observations turned doubt into discovery, and his courage to question reshaped our view of the cosmos.

The same spirit animated Charles Darwin, whose theory of evolution refined rather than rejected scientific tradition. Both men faced fierce resistance for questioning ideas that constrained knowledge, yet their scepticism was guided by evidence, not defiance. This selective doubt, focused on understanding rather than destruction, is what fuels intellectual progress.

The stories of Galileo and Darwin are not unique. Each generation has found new forms of authority to question and new assumptions to overturn. What begins as individual acts of courage becomes the foundation of an age; an age where reason, not revelation, become the measure of truth.

Scientific advancement and the challenge to dogma

Progress in science has always begun with doubt; doubt directed at explanations that no longer fit the evidence. The heliocentric model overturned centuries of scriptural certainty, replacing divine design with natural order. Darwin extended that revolution to life itself, tracing creation to the slow logic of evolution rather than the sudden word of God. Pasteur, by identifying invisible pathogens instead of divine punishment, transformed medicine. And when Einstein and the early quantum theorists questioned Newton’s absolutes, they revealed a universe more complex and dynamic than anyone had imagined.

Each breakthrough followed the same pattern: a challenge to dogma, an allegiance to evidence, and a redefinition of what it means to know. The Enlightenment gathered these impulses into a movement, replacing revelation with reason as humanity’s guiding light. As historian Richard Westfall, best known for his studies of Newton and the Scientific Revolution, observed, this shift did not destroy faith so much as relocate wonder – from the heavens to the human mind.

Without such scrutiny, societies stagnate, bound by the certainties they mistake for truth. Targeted scepticism, aimed not at meaning itself but at unfounded claims, creates the conditions for discovery, freeing enquiry from the shadow of divine authority.

Yet even the light of reason casts its own shadow. Every age that dismantles one form of dogma risks constructing another in its place. The same critical spirit that liberated science from superstition can, when left unchecked, harden into its own creed. The challenge is not only to question authority, but also to ensure that reason itself remains accountable to compassion, humility and doubt.

When reason needs reflection

Reason, too, must be doubted. It has carried humanity from superstition to discovery, yet it falters when it forgets its own limits. History offers sobering reminders: ideas once celebrated as progress – such as eugenics – show how logic, when stripped of empathy, can justify cruelty. The failure was not in calculation but in conscience, a blindness born of intellect untempered by humility.

Early Utilitarians such as Bentham made a similar mistake when they reduced morality to mathematics. In seeking to maximise happiness, they sometimes sacrificed individual dignity – proof that pure reason, without compassion, can miss the mark.

Even today’s secular societies, enthralled by data and efficiency, risk a new form of faith: the conviction that logic alone can explain everything. Such certainty, ironically, mirrors the very dogma scepticism seeks to replace.

Non-belief, then, should not be mistaken for ideological immunity. The absence of faith does not guarantee the presence of wisdom. Scepticism works best not as demolition but as renovation; refining ideas through reflection rather than replacing one certainty with another. Guided by humility and emotional intelligence, reason becomes not only a tool for enquiry but a compass for compassion.

Ethics by design

Once reason turns its gaze from the cosmos to the human condition, enquiry becomes a moral act. Constructive doubt evolves into design – building frameworks of empathy, justice and responsibility. Secular philosophies such as humanism rest on that foundation, replacing divine command with ethical reasoning grounded in shared human experience. Across history, sceptics and reformers have drawn on this moral imagination to challenge oppression and expand the circle of compassion.

Morality, rather than being dictated by supernatural decree, has evolved through critical reasoning and collective human experience. Ethical frameworks based on compassion and logical consistency ensure that principles can adapt to societal progress rather than remain bound to sacred texts.

For example, movements for LGBTQ+ rights, reproductive freedom and racial justice have often faced resistance from religious institutions, according to research by the Pew Research Center. However, secular voices have championed personal autonomy and ethical reasoning, arguing that morality should be based on human well-being rather than adherence to ancient doctrines.

Furthermore, rejecting divine authority can empower individuals to take responsibility for their actions rather than attributing fate to supernatural forces. If morality is not dictated by a higher power, people must construct ethical frameworks based on rational thought and compassion. This autonomy encourages accountability, placing humanity at the centre of moral decision-making.

In taking moral responsibility for ourselves, we inherit not just duty but freedom. When ethics are grounded in human reason rather than divine decree, conscience becomes an act of creativity; an ongoing experiment in how to live well together. That experiment extends beyond morality into well-being itself, shaping how nonbelievers find purpose, connection, and meaning without faith.

Flourishing without faith

While religion has long offered comfort and community, non-belief brings its own kind of flourishing – one rooted in intellectual freedom and self-determined meaning. Rational thinkers are less likely to fear divine punishment, which can lead to a greater sense of personal control and emotional resilience. Rather than relying on prayer or divine intervention, nonbelievers often cultivate self-reliance, seeking solutions through logic and reason.

According to Phil Zuckerman’s research in Society Without God (2008), secular societies often display higher education levels, lower crime rates, and increased gender equality, evidence that rational governance and non-belief can foster human flourishing.

Countries with higher percentages of atheists often invest more in scientific research, social welfare, and human rights, demonstrating the societal advantages of rational, reason-based decision-making.

Moreover, non-belief fosters inclusivity. By removing religious barriers, individuals from diverse backgrounds can unite under shared ethical principles rather than theological divisions. A secular approach to governance promotes policies based on universal human needs rather than religious doctrines, ensuring fairness and equality across populations.

Yet the true measure of a secular society is not only in its fairness, but in its curiosity. A world governed by reason still hungers for wonder. Freed from divine command, we are left with the task of creating meaning through understanding – a search that continues the oldest human project of all: to know ourselves and the universe we inhabit.

Questioning leads to progress

Non-belief is more than a rejection of gods; it’s the continuation of humanity’s oldest enquiry: the search for truth through understanding. While faith has long provided cultural cohesion, it is scepticism that has propelled humanity forward, challenging outdated assumptions and driving scientific, ethical and social evolution.

Critical thinking offered survival advantages from the start, and today it remains a force for transformation, from the adaptive edge of early enquiry to the broad-reaching influence of secular governance. The evolutionary advantage of non-belief lies not in blanket doubt, but in the precision of questioning.

Instead of promoting doubt as a default stance, we should champion constructive questioning, scrutinising what lacks evidence while preserving valuable insight. Advancement depends not on negation, but on intellectual evolution.

This pursuit of truth is among humanity’s greatest strengths. Scepticism isn’t mere doubt, it’s the catalyst that fuels discovery, dismantles dogma, and expands the boundaries of understanding. Where faith settles into answers, reason unfolds in questions, and it’s the questions that open the universe.

In a world flooded with information, it is not belief or disbelief that defines our future, but the courage to ask wisely, and to keep asking.