No problem can withstand the assault of sustained thinking.
~Voltaire

Reading without reflecting is like eating without digesting.
~Edmund Burke

Often the hands will solve a mystery that the intellect has struggled with in vain.
~Carl G. Jung

Never be afraid to sit awhile and think.
~Lorraine Hansberry, A Raisin in the Sun

No matter where you go or what you do, you live your entire life within the confines of your head.
~Terry Josephson

You and I are not what we eat; we are what we think.
~Walter Anderson, The Confidence Course, 1997

Did you ever stop to think, and forget to start again?
~Winnie the Pooh

People demand freedom of speech as a compensation for the freedom of thought which they seldom use.
~Soren Kierkegaard

Too often we... enjoy the comfort of opinion without the discomfort of thought.
~John F. Kennedy

The trouble with most people is that they think with their hopes or fears or wishes rather than with their minds.
~Will Durant

Begin challenging your own assumptions. Your assumptions are your windows on the world. Scrub them off every once in awhile, or the light won't come in.
~Alan Alda

I like to think of thoughts as living blossoms borne by the human tree.
~James Douglas

The forceps of our minds are clumsy things and crush the truth a little in the course of taking hold of it.
~H.G. Wells

Our minds are lazier than our bodies.
~François, Duc de La Rochefoucauld, Maxims, 1678

Invest a few moments in thinking. It will pay good interest.
~Author Unknown

Some people get lost in thought because it's such unfamiliar territory.
~G. Behn

Thinking is like loving and dying. Each of us must do it for himself.
~Josiah Royce

It is well for people who think, to change their minds occasionally in order to keep them clean.
~Luther Burbank

Physiological response to thinking and to pain is the same; and man is not given to hurting himself.
~Martin H. Fischer

We spend our days in deliberating, and we end them without coming to any resolve.
~L'Estrange

Our job is not to make up anybody's mind, but to open minds and to make the agony of the decision-making so intense you can escape only by thinking.
~Author Unknown

Thinking in its lower grades is comparable to paper money, and in its higher forms it is a kind of poetry.
~Havelock Ellis, The Dance of Life, 1923

The average man never really thinks from end to end of his life. The mental activity of such people is only a mouthing of clichés.
~H.L. Mencken, Prejudices, 1925

Few people think more than two or three times a year; I have made an international reputation for myself by thinking once a week.
~George Bernard Shaw

...the thoughtful excitement of lonely rambles, of gardening, and of other like occupations, where the mind has leisure to must during the healthful activity of the body, with the fresh and wakeful breezes blowing round it...
~Augustus William Hare and Julius Charles Hare, Guesses at Truth, by Two Brothers, 1827

Belief is when someone else does the thinking.
~Buckminster Fuller, 1972

Irons rusts from disuse, stagnant water loses its purity and in cold weather becomes frozen; even so does inaction sap the vigor of the mind.
~Leonardo da Vinci, Notebooks, 1508

A sect or party is an elegant incognito devised to save a man from the vexation of thinking.
~Ralph Waldo Emerson

Thoughts, like fleas, jump from man to man. But they don't bite everybody.
~Stanislaw Lec, Unkempt Thoughts, 1962

Nothing is more conducive to peace of mind than not having any opinion at all.
~G.C. Lichtenberg

The world we have created is a product of our thinking; it cannot be changed without changing our thinking.
~Albert Einstein

Brain, n. An apparatus with which we think that we think.
~Ambrose Bierce, The Devil's Dictionary

At a certain age some people's minds close up; they live on their intellectual fat.
~William Lyon Phelps

Thought is the wind, knowledge the sail, and mankind the vessel.
~Augustus William Hare and Julius Charles Hare, Guesses at Truth, by Two Brothers, 1827

No amount of energy will take the place of thought. A strenuous life with its eyes shut is a kind of wild insanity.
~Henry Van Dyke

Tell your friends not to think aloudUntil they swallow.
~Nickelback, "Leader of Men," The State

Believing is easier than thinking. Hence so many more believers than thinkers.
~Bruce Calvert

A man is not idle because he is absorbed in thought. There is a visible labor and there is an invisible labor
~Victor Hugo

Sometimes I think and other times I am.
~Paul Valéry, Variété: Cantiques spirituels, 1924

Few minds wear out; more rust out.
~Christian N. Bovee

Opinion is that exercise of the human will which helps us to make a decision without information.
~John Erskine

Some people do not become thinkers simply because their memories are too good.
~Friedrich Wilhelm Nietzsche

Men can live without air a few minutes, without water for about two weeks, without food for about two months - and without a new thought for years on end.
~Kent Ruth

The thoughts that come often unsought, and, as it were, drop into the mind, are commonly the most valuable of any we have.
~John Locke, 16 May 1699

Men who borrow their opinions can never repay their debts.
~George Savile, Marquess de Halifax, Miscellaneous Thoughts and Reflections

A lawyer's brief will be brief, before a freethinker thinks freely.
~Augustus William Hare and Julius Charles Hare, Guesses at Truth, by Two Brothers, 1827

Chi Wen Tzu always thought three times before taking action. Twice would have been quite enough.
~Confucius, Analects

Impartial observers from other planets would consider ours an utterly bizarre enclave if it were populated by birds, defined as flying animals, that nevertheless rarely or never actually flew. They would also be perplexed if they encountered in our seas, lakes, rivers, and ponds, creatures defined as swimmers that never did any swimming. But they would be even more surprised to encounter a species defined as a thinking animal if, in fact, the creature very rarely indulged in actual thinking.
~Steve Allen

What luck for rulers, that men do not think.
~Adolph Hitler

Doubt is not a pleasant state of mind, but certainty is absurd.
~Voltaire, 1767

Men fear thought as they fear nothing else on earth, more than ruin, more even than death. Thought is subversive and revolutionary, destructive and terrible, thought is merciless to privilege, established institutions, and comfortable habit. Thought looks into the pit of hell and is not afraid. Thought is great and swift and free, the light of the world, and the chief glory of man.
~Bertrand Russell

[Thinking is] what a great many people think they are doing when they are merely rearranging their prejudices.
~William James

For those who do not think, it is best at least to rearrange their prejudices once in a while.
~Luther Burbank

How wonderful that we have met with a paradox. Now we have some hope of making progress.
~Niels Bohr

You cannot plough a field by turning it over in your mind.
~Author Unknown

He who will not reason is a bigot; he who cannot is a fool; and he who dares not is a slave.
~William Drummond, Academical Questions

Ours is the age which is proud of machines that think and suspicious of men who try to.
~Howard Mumford Jones