Skeptical (and not so skeptical) Quotations

These are quotations concerning skepticism, science, belief, faith and related topics. They're not all necessarily skeptical, as some may better serve to remind skeptics that even our approach of scientific and critical inquiry can be questioned. And at least one quotation is outright hostile to skepticism (but it's funny!).  — Eric

Click on a name or just scroll down and browse them in random order:

 
It is wrong always and everywhere for anyone to believe anything on insufficient evidence.

William Kingdon Clifford, mathematician, philosopher
"The Ethics of Belief", 1879

Known as "Clifford's Dictum" this is one of two quotations adopted by Ontario Skeptics Society for Critical Inquiry (OSSCI).

 
There is no other species on Earth that does science. It is, so far, entirely a human invention, evolved by natural selection in the cerebral cortex for one simple reason: it works. It is not perfect. It can be misused. It is only a tool. But it is by far the best tool we have, self-correcting, ongoing, applicable to everything.

Carl Sagan, scientist, science popularizer
Cosmos, 1980

This is the other quotation adopted by OSSCI in its mission statement.

 
A belief which leaves no place for doubt is not a belief; it is a superstition.

José Bergamín, writer
The Rocket and the Star, 1923

Skepticism is provisional, even if it lasts a lifetime.

Head in the Clouds, 1934

 
Belief in the truth commences with the doubting of all those “truths” we once believed.

Friedrich Nietzsche, philosopher
“Truth Will Have No Other Gods Alongside It,” 1879

 
Faith: Belief without evidence in what is told by one who speaks without knowledge, of things without parallel.

Ambrose Bierce, writer
The Devil’s Dictionary, 1881-1906

 
Belief is nothing but a more vivid, lively, forcible, firm, steady conception of an object, than what the imagination alone is ever able to attain.

David Hume, philosopher
Enquiries Concerning the Human Understanding and Concerning the Principles of Morals

So, like, is that a good thing or a bad thing? 

 
No actual skeptic, so far as I know, has claimed to disbelieve in an objective world. Skepticism is not a denial of belief, but rather a denial of rational grounds for belief.

William Pepperell Montague, philosopher
“The Story of American Realism”, 1937

 
The same principles which at first view lead to skepticism, pursued to a certain point, bring men back to common sense.

George Berkeley, philosopher

Three Dialogues Between Hylas and Philonous, 1713

The advantages of selective quoting! This makes Berkeley sound like one of us (a skeptic). In fact, he was arguing that philosophical arguments of his time against the existence of an external reality bring one around to accepting the need for a Supreme Being.

 
I would rather have a mind opened by wonder than one closed by belief.

Gerry Spence, lawyer
How to Argue and Win Every Time, 1995

 
Mystical experience and asceticism. The fornicator's hatred of life in a new form.

Aldous Huxley, novelist

Rampion in Point Counter Point, 1928

Of course, Aldous Huxley himself became a mystic in later life. Fornication will do that to you.

 
The improver of natural knowledge absolutely refuses to acknowledge authority, as such. For him, skepticism is the highest of duties; blind faith the one unpardonable sin.

Thomas Henry Huxley, biologist and educator

Aphorisms and Reflections, 1907

 
The word “belief” is a difficult thing for me. I don’t believe. I must have a reason for a certain hypothesis. Either I know a thing, and then I know it—I don’t need to believe it.

Carl Jung, psychiatrist
Interview in Hugh Burnett, Face to Face, 1959

Sounds good. Yet Jung held many very strange beliefs concerning the occult. Not to mention his often bizarre theories concerning the subconscious, collective consciousness, archetypes and other psychoanalytical claptrap. 

 
The essence of belief is the establishment of a habit; and different beliefs are distinguished by the different modes of action to which they give rise.

Charles Sanders Peirce, philosopher
“How to Make Our Ideas Clear”, 1978

 
I fear I shall remain one of those who believe in spirits much too easily ever to become a spiritualist. Modern people think the supernatural so improbable that they want to see it. I think it so probable that I leave it alone. Spirits are not worth all this fuss; I know that, for I am one myself.

G.K. Chesterton, writer
“Skepticism and Spiritualism”, 1906

 
“Skepticism”  — is that anything more than we used to mean when we said, “Well, what have we here?”

Robert Frost, poet
Quoted in Partisan Review, 1946 

 
Life itself is a bubble and a skepticism, and a sleep within sleep.

Ralph Waldo Emerson, essayist and philosopher
Essays, Second Series, 1844

No, I haven't got a clue either what this means. Sounds beautiful though.

A just thinker will allow full swing to his skepticism. I dip my pen in the blackest ink, because I am not afraid of falling into my inkpot.

The Conduct of Life, 1860

 
The poison of skepticism becomes, like alcoholism, tuberculosis, and some other diseases, much more virulent in a hitherto virgin soil.

Simone Weil, mystic
“East and West”, 1943

Ouch. She really got us alcoholic, tubercular skeptics there. 

 
There are more things in heaven and earth, Horatio, than are dreamt of in your philosophy.

William Shakespeare, playwright
Hamlet in Hamlet, 1601

The fault, dear Brutus, is not in our stars, but in ourselves.

Cassius in Julius Caesar, 1599

Shakespeare is like the Bible — you can find quotes in his writing to support almost any position. Ah, well, we might as well use him for the skeptical side too.

 
These matters require what I think of as the Shakespearean cast of thought. That is to say, a fine credulity about everything, kept in check by a lively skepticism about everything.... It keeps you constantly alert to every possibility.

Robertson Davies, novelist
Hugh McWearie in Murther and Walking Spirits, 1991

 
There is no absolute knowledge. And those who claim it, whether they are scientists or dogmatists, open the door to tragedy. All information is imperfect. We have to treat it with humility.

Jacob Bronowski, scientist, broadcaster
The Ascent of Man, 1973

I wonder if he was absolutely certain of this.

 
Dogmatism and skepticism are both, in a sense, absolute philosophies; one is certain of knowing, the other of not knowing. What philosophy should dissipate is certainty, whether of knowledge or ignorance.

Bertrand Russell, philosopher, mathematician
“Philosophy for the Layman,” Unpopular Essays, 1950

The skepticism that Russell decries is that variety of philosophical skepticism that says it is impossible for us to know anything. Many skeptics today, who consider our beliefs provisional as based on available evidence, can agree with this attack on absolutism.

William James used to preach the "will to believe". For my part, I should wish to preach the "will to doubt".... What is wanted is not the will to believe, but the will to find out, which is the exact opposite.

Skeptical Essays, 1928

 
I cannot give any scientist of any age better advice than this: the intensity of a conviction that a hypothesis is true has no bearing on whether it is true. The importance of the strength of our conviction is only to provide a proportionately strong incentive to find out if the hypothesis will stand up to critical examination.

Peter B. Medawar, zoologist and immunologist
Advice to a Young Scientist, 1979

 
Our human ability to see positive cases and inability to see negative ones tends to put us all in the position of the fool who believed that everybody spoke the same language as he did, because he had never met anybody who didn't.

Richard Kammann, psychologist
The Psychology of the Psychic, co-authored with David Marks, 1980

 
I do not believe in ghosts. I believe in ghost stories.

John Robert Colombo, writer, editor
"Certain Aphorisms of John Robert Colombo"

 
And for the ultimate word on belief, a definition of a new religion from a famous philosopher:

Frisbeetarianism is the belief that when you die, your soul goes up on the roof and gets stuck.

George Carlin, comedian