Werner Heisenberg Quotes

I hold that the propositions embodied in natural science are not derived by any definite rule from the data of experience, and that they can neither be verified nor falsified by experience according to any definite rule.

I think philosophers can do things akin to theoretical scientists, in that, having read about empirical data, they too can think of what hypotheses and theories might account for that data. So there's a continuity between philosophy and science in that way.

All phenomena] are equally susceptible of being calculated, and all that is necessary, to reduce the whole of nature to laws similar to those which Newton discovered with the aid of the calculus, is to have a sufficient number of observations and a mathematics that is complex enough.

In order that the facts obtained by observation and experiment may be capable of being used in furtherance of our exact and solid knowledge, they must be apprehended and analysed according to some Conceptions which, applied for this purpose, give distinct and definite results, such as can be steadily taken hold of and reasoned from.

In so far as such a theory is empirically correct it will also tell us what empirical facts it should be possible to observe in a given set of circumstances.

Science is objective. And in my view we cannot take any experimental results seriously except in the light of good explanations of them.

The situation in the sciences is this: A concept or an idea which cannot be measured or cannot be referred directly to experiment may or may not be useful. It need not exist in a theory.

To be radical, an empiricism must neither admit into its constructions any element that is not directly experienced, nor exclude from them any element that is directly experienced.

Hypotheses should be subservient only in explaining the properties of things but not assumed in determining them, unless so far as they may furnish experiments.

Not as a demonstrated natural law, but as a working hypothesis.

In a few decades of reconstruction, even the mathematical natural sciences, the ancient archetypes of theoretical perfection, have changed habit completely!

We would be in a nasty position indeed if empirical science were the only kind of science possible.

That is, a system starts with a group of interrelated propositions which involve reference to empirical observations within the logical framework of the propositions in question.

Scientific theory is a contrived foothold in the chaos of living phenomena.

The proper method for inquiring after the properties of things is to deduce them from experiments.

Rationalism, which is the feeling that everything is subject to and completely explicable by Reason, consequently rejects everything not visible and calculable.

Experience seems to most of us to lead to conclusions, but empiricism has sworn never to draw them.

In the discovery of secret things and in the investigation of hidden causes, stronger reasons are obtained from sure experiments and demonstrated arguments than from probable conjectures and the opinions of philosophical speculators of the common sort.

A few observation and much reasoning lead to error; many observations and a little reasoning to truth.

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

Science, incidentally, not only ignores the question of indwelling 'essences' by looking instead at measurable relationships, but science also does not agree that knowledge is obtained through Rothbard's Medieval 'investigation by a reason,' i.e., by inventing definitions and then deducing what your definitions implicitly assumed.

Whether or not you can observe a thing depends upon the theory you use. It is the theory which decides what can be observed.

I am not a positivist. Positivism states that what cannot be observed does not exist. This conception is scientifically indefensible, for it is impossible to make valid affirmations of what people 'can' or 'cannot' observe. One would have to say 'only what we observe exists,' which is obviously false.

Science, in its ultimate ideal, consists of a set of propositions arranged in a hierarchy, the lowest level of the hierarchy being concerned with particular facts, and the highest with some general law, governing everything in the universe. The various levels in the hierarchy have a two-fold logical connection, travelling one up, one down; the upward connection proceeds by induction, the downward by deduction.

For the theory-practice iteration to work, the scientist must be, as it were, mentally ambidextrous; fascinated equally on the one hand by possible meanings, theories, and tentative models to be induced from data and the practical reality of the real world, and on the other with the factual implications deducible from tentative theories, models and hypotheses.