Logical Inference Quotes

The simplest explanation is always the most likely.

Deduction, which takes us from the general proposition to facts again-teaches us, if I may so say, to anticipate from the ticket what is inside the bundle.

Facts - behind them lies the whole fabric of deductive truth.

Induction for deduction, with a view to construction.

Neither Aristotelian nor Russellian rules give the exact logic of any expression of ordinary language; for ordinary language has no exact logic.

Logic, n. The art of thinking and reasoning in strict accordance with the limitations and incapacities of the human misunderstanding. The basic of logic is the syllogism, consisting of a major and a minor premise and a conclusion - thus: Major Premise: Sixty men can do a piece of work sixty times as quickly as one man. Minor Premise: One man can dig a post-hole in sixty seconds; Therefore- Conclusion: Sixty men can dig a post-hole in one second. This may be called syllogism arithmetical, in which, by combining logic and mathematics, we obtain a double certainty and are twice blessed.

So my antagonist said, "Is it impossible that there are flying saucers? Can you prove that it's impossible?" "No," I said, "I can't prove it's impossible. It's just very unlikely." At that he said, "You are very unscientific. If you can't prove it impossible then how can you say that it's unlikely?" But that is the way that is scientific. It is scientific only to say what is more likely and what less likely, and not to be proving all the time the possible and impossible.

The one [the logician] studies the science of drawing conclusions, the other [the mathematician] the science which draws necessary conclusions.

He that in the ordinary affairs of life would admit of nothing but direct plain demonstration would be sure of nothing in this world but of perishing quickly.

It would be superfluous to receive by faith, things that can be known by natural reason

Inductive inference is the only process known to us by which essentially new knowledge comes into the world.

After all, once you know that part of something exists, it stands to reason that the rest of it is somewhere out there, too.

The example of a syllogism that he had studied in Kiesewetter's logic: Caius is a man, men are mortal, therefore Caius is mortal, had throughout his whole life seemed to him right only in relation to Caius, but not to him at all.

There is nothing which an untrained mind shows itself more hopelessly incapable, than in drawing the proper general conclusions from its own experience. And even trained minds, when all their training is on a special subject, and does not extend to the general principles of induction, are only kept right when there are ready opportunities of verifying their inferences by facts.

All possible knowledge, then, depends on the validity of reasoning. Unless human reasoning is valid, no science can be true.

One can't proceed from the informal to the formal by formal means.

Without deductive logic science would be entirely useless. It is merely a barren game to ascend from the particular to the general, unless afterwards we can reverse the process and descend from the general to the particular, ascending and descending like angels on Jacob's ladder.

To disparage the dictate of reason is equivalent to contemning the command of God.

There is no sphere in which a human being can be supposed to act where one mode of reasoning will not, in every given instance, be more reasonable than any other mode. That mode the being is bound by every principle of justice to pursue.

If logic itself is created rather than being inborn, it follows that the first task of education is to form reasoning.

Riposte of "that old lady in the anecdote who was accused by her nieces of being illogical," Logic! Good gracious! What rubbish! How can I tell what I think till I see what I say?

If you make the same guess often enough it ceases to be a guess and becomes a Scientific Fact. This is the inductive method.

However logical our induction, the end of the thread is fastened upon the assurance of faith.

The physicist, in his study of natural phenomena, has two methods of making progress: (1) the method of experiment and observation, and (2) the method of mathematical reasoning. The former is just the collection of selected data; the latter enables one to infer results about experiments that have not been performed. There is no logical reason why the second method should be possible at all, but one has found in practice that it does work and meets with reasonable success.

A rational prediction has an explanation based on theory.