There is arguably nothing more important to the world than critical thought. It is critical thought that causes us to pause before doing what we are told. Without critical thinking, we are mere pawns of our lower passions and the commands of authority. With critical thinking, we become our own masters.

What’s more, it is a lack of critical thinking that is responsible for a number of atrocities, both big and small. Few things in the world are more dangerous than a mass of men who have decided not to think for themselves. While we cannot control the actions of others, we can begin making the world a better place simply by thinking for ourselves and encouraging others to do the same.

This is why the powerful always seek to censor freedom of speech. Free access to free ideas is kryptonite to those who would be tyrants. It is important that we are confronted with ideas that make us uncomfortable, if only because it serves to make our own convictions more deeply held, more nuanced and more adaptable to new information.

An attack on freedom of speech is an attack on our facilities of critical thinking itself.

These are some of our favorite quotes on critical thinking and free speech from some of the greatest minds in history.

Quotes About Critical Thinking and the Lack of Critical Thinking


Aristotle quote on critical thinking

“It is the mark of an educated mind to be able to entertain a thought without accepting it.”



Eric Hoffer quote on critical thinking


“You can discover what your enemy fears most by observing the means he uses to frighten you.”

Eric Hoffer


Voltaire quote on critical thinking


“Those who can make you believe absurdities can make you commit atrocities.”



Carl Jung quote on critical thinking


“…the relatively unconscious man driven by his natural impulses because, imprisoned in his familiar world, he clings to the commonplace, the obvious, the probable, the collectively valid, using for his motto: ‘Thinking is difficult. Therefore, let the herd pronounce judgement.'”

Carl Jung, Psychology and Religion: West and East


Andrei Sakharov quote on critical thinking


“Do not trust governments more than governments trust their own people.”

Andrei Sakharov


A. Hofmann quote on critical thinking


“I will listen to any hypothesis but on one condition — that you show me a method by which it can be tested.”

August Wilhelm von Hofmann


James Mattis quote on critical thinking


“Engage your brain before you engage your weapon.”

General James Mattis


Jose Marti quote on critical thinking


“The first duty of a man is to think for himself.”

Jose Marti


Rod Serling quote on critical thinking


“We’re developing a new citizenry. One that will be very selective about cereals and automobiles, but won’t be able to think.”

Rod Serling


Unknown quote on critical thinking


“Even a broken clock is right twice a day.”



Schopenhauer quote on critical thinking


“The majority of men… are not capable of thinking, but only of believing, and… are not accessible to reason, but only to authority.”

Arthur Schopenhauer


Unknown quote on critical thinking


“Life is fraught with opportunities to keep your mouth shut.”

– Unknown, often misattributed to Winston Churchill


W. Churchill quote on critical thinking


“Men occasionally stumble over the truth, but most of them pick themselves up and hurry off as if nothing had happened.”

Winston Churchill


Thomas Paine quote on critical thinking


“It is the duty of everyman, so far as his ability allows, to detect and expose delusion and error.”

Thomas Paine


Niccolò Machiavelli quote on critical thinking


“There are three classes of intellects: one which comprehends by itself; another which appreciates what others comprehend; and a third which neither comprehends by itself nor by the showing of others; the first is the most excellent, the second is good, and the third is useless.”

Niccolò Machiavelli


Albert Camus quote on critical thinking


“The evil that is in the world almost always comes of ignorance, and good intentions may do as much harm as malevolence if they lack understanding.”

Albert Camus


Jim Rohn quote on critical thinking


“We need to teach our children how to debate the major life issues. Debate strengthens their beliefs and enables them to defend themselves against ideologies that are going to come their way.”

Jim Rohn, The Treasury of Quotes


Jim Rohn quote on critical thinking


“One of the great liberal documents of the world is the Declaration of Independence. One of the great conservative documents of the world is the Constitution of the United States. We need both documents to build a country. One to get it started – liberal. And the other to help maintain the structure over the years – conservative.”

Jim Rohn


Joseph de Maistre quote on critical thinking


“False opinions are like false money, struck first of all by guilty men and thereafter circulated by honest people who perpetuate the crime without knowing what they are doing.”

Joseph de Maistre