Carl Sagan Quotes

It is not observation but theory that led me to this result that experience has confirmed afterwards.

Physics is unable to stand on its own feet, but needs a metaphysics on which to support itself, whatever fine airs it may assume towards the latter.

We must trust to nothing but facts: these are presented to us by nature and cannot deceive. We ought, in every instance, to submit our reasoning to the test of experiment, and never to search for truth but by the natural road of experiment and observation.

My background is basically scientific math. My Dad was a physicist, so I have it in my blood somewhere. Scientific method is very important to me. I think anything that contradicts it is probably not true.

Philosophers have not kept up with modern developments in science. Particularly physics.

I think that in the discussion of natural problems we ought to begin not with the Scriptures, but with experiments, and demonstrations.

The strongest arguments prove nothing so long as the conclusions are not verified by experience. Experimental science is the queen of sciences and the goal of all speculation.

To me, what makes physics physics is that experiment is intimately connected to theory. It's one whole.

In experimental philosophy, we are to look upon propositions inferred by general induction from phenomena as accurately or very nearly true, notwithstanding any contrary hypotheses that may be imagined, till such time as other phenomena occur by which they may either be made more accurate or liable to exceptions.

The specious figments of genius, and the erratic flights of philosophy, may excite our wonder, but they cannot stand the ordeal of scrutiny, or the Lydian touch of experiment.

What is the fundamental hypothesis of science, the fundamental philosophy? We stated it in the first chapter: the sole test of the validity of any idea is experiment. ... If we are told that the same experiment will always produce the same result, that is all very well, but if when we try it, it does not, then it does not. We just have to take what we see, and then formulate all the rest of our ideas in terms of our actual experience.

Science walks forward on two feet, namely theory and experiment. Sometimes it is one foot which is put forward first, sometimes the other, but continuous progress is only made by the use of both.

Metaphysics is a cobweb that the mind weaves around things.

In the philosophic sense, observation shows and experiment teaches.

Philosophy treats of physics where a more careful knowledge is required because the problems which come under this head are numerous... So the reader of Ctesibius or Archimedes and the other writers of treatises of the same class will not be able to appreciate them unless he has been trained in these subjects by the philosophers.

Different ‘philosophies’ represent nothing but methods of evaluation, which may lead to empirical mis-evaluation if science and empirical facts are disregarded.

It is the facts that matter, not the proofs. Physics can progress without the proofs, but we can't go on without the facts ... if the facts are right, then the proofs are a matter of playing around with the algebra correctly.

As for me, I have just enough confidence about the multiverse to bet the lives of both Andrei Linde and Martin Rees’s dog.

Philosophy stands in need of a science which shall determine the possibility, principles, and extent of human knowledge à priori.

To mix science up with philosophy is only to produce a philosophy that has lost all its ideal value and a science that has lost all its practical value. It is for my private physician to tell me whether this or that food will kill me. It is for my private philosopher to tell me whether I ought to be killed.

It is within science itself, and not in some prior philosophy, that reality is to be identified and described.

We must reason in natural philosophy not from what we hope, or even expect, but from what we perceive.

Born and nurtured when the human being first asked questions about the reason for things and their purpose, philosophy shows in different modes and forms that the desire for truth is part of human nature itself.

Every science begins as philosophy and ends as art; it arises in hypothesis and flows into achievement.

Science is a combination of theory and experiment and the two together are how you make progress.