Quotes About Logic

The art of number theory is so abstract that it is frighteningly easy to wander off the path of logic and be completely unaware that one has strayed into absurdity

The construction of mathematical logic had become the arbiter of truth. This was the Pythagoreans' greatest contribution to civilisation - a way of achieving truth which is beyond the fallibility of human judgement.

People say you have to have faith because believing is irrational. So I end up thinking that the more irrational things seem, the more likely they are to be true.

Yet what is impossible in logic becomes true in life, and the contradiction lodged within the soul tears it to shreds.

But it is serpentine logic, for it simply compounds the old legal spirit. It is the natural instinct of the once-antinomian prodigal who, when awakened, thinks in terms of working his way back into the favor of his father.38

This same distortion appears when the gospel is preached to the natural man. Boston was all too familiar with the instinct of the awakened individual to say, "I will now try much harder, and I will do better." It seems logical: I realize I have failed. I must reverse this failure by doing better. But it is serpentine logic, for it simply compounds the old legal spirit.

The world's most famous fictional detective, Sherlock Holmes, said that once you have eliminated all the possibilities, whatever remains, however improbable, must be true.

If I claim full justice for my art, it is because it is an impersonal thing—a thing beyond myself. Crime is common. Logic is rare. Therefore it is upon the logic rather than upon the crime that you should dwell. You have degraded what should have been a course of lectures into a series of tales.

Crime is common. Logic is rare. Therefore it is upon the logic rather than upon the crime that you should dwell.

The emotional qualities are antagonistic to clear reasoning.

It is a capital mistake to theorise before one has data.

Crime is common. Logic is rare.

Sir Arthur Conan Doyle

Women have seldom have been an attraction to me, for my brain has always governed my heart.

It is an old maxim of mine that when you have excluded the impossible, whatever remains, however improbable, must be the truth.

Mi querido Watson, no estoy de acuerdo con los que opinan que la modestia es una virtud. Para la mente lógica, todo debería verse exactamente tal como es, y subestimarse es algo tan lejano de la realidad como exagerar nuestras propias facultades.

when you have eliminated the impossible, whatever remains, however improbable, must be the truth? (The Sign of the Four, page 111)

I reached this one, said my friend, by sitting upon five pillows and consuming an ounce of shag. I think, Watson, that if we drive to Baker-street we shall just be in time for breakfast.

In solving a problem of this sort, the grand thing is to be able to reason backwards. That is a very useful accomplishment, and a very easy one, but people do not practice it much.

If you eliminate all other possibilities, whatever remains must be the truth. Sherlock Holmes

When you have eliminated the impossible, whatever remains, however improbable, must be the truth.

É arriscado especular antes de ter dados na mão...inconscientemente começa-se a torcer os factos para os acomodar às teorias, em vez de fazer as teorias coincidirem com os factos.

Alas! How sad when reasoners reason wrong.

How sad when those who reason, reason wrong.