A Quote by Bertrand Russell

A priori Logical propositions are such as can be known a priori without study of the actual world.

Bertrand Russell

Quote Topics

Actual Known Logical Propositions Study Without World

Quote Author

Bertrand Russell
British - Celebrity
May 18, 1872 - February 2, 1970

We can pursue the Cartesian project without restricting ourselves to theology and a priori faculties. A better, broader perspective is properly sought if we pursue the project with reliance on science broadly and on our full span of epistemic competences, including the empirical as well as the a priori.

Ernest Sosa

Natural science physics contains in itself synthetical judgments a priori, as principles. ... Space then is a necessary representation a priori, which serves for the foundation of all external intuitions.

Immanuel Kant

Notwithstanding their attacks on the basic conception of rationalism, on synthetic a priori judgments, that is, material propositions that cannot be contradicted by any experience, the empiricist posits the forms of being as constant.

Max Horkheimer

Science asks no questions about the ontological pedigree or a priori character of a theory, but is content to judge it by its performance; and it is thus that a knowledge of nature, having all the certainty which the senses are competent to inspire, has been attained--a knowledge which maintains a strict neutrality toward all philosophical systems and concerns itself not with the genesis or a priori grounds of ideas.

Chauncey Wright

What I most cherish is the observation of the movement of colors. Only in this have I found the laws of those simultaneous and complementary color contrasts that nourish the actual rhythm of my vision. In this I find the actual essence, an essence which is not born out of an a priori system or theory.

August Macke

Wherever Mathematics is mixed up with anything, which is outside its field, you will find attempts to demonstrate these merely conventional propositions a priori, and it will be your task to find out the false deduction in each case.

Carl Gustav Jacob Jacobi

It is possible to demonstrate God's existence, although not a priori, yet a posteriori from some work of His more surely known to us.

Thomas Aquinas

In philosophical terms, the opposite of rationalism is not irrationalism but empiricism, that is, a willingness to form beliefs on the basis of experience rather than from a priori deduction. Empirical evidence never yields the dogmatic certainty that accompanies logical deduction.

John Quiggin

We no longer see the evolution of the nervous system, but that of a certain individual. The role of the memory is very important but... not as important as we believe. Most of the important things that we do don't depend on memory. To hear, to see, to touch, to feel happiness and pain; these are functions which are independent of memory; it is an a priori thing. Thus, for me, what memory does is to modify that a priori thing, and this it does in a very profound way.

Rodolfo Llinas

Often one postulates that a priori, all states are equally probable. This is not true in the world as we see it. This world is not correctly described by the physics which assumes this postulate.

Richard P. Feynman

The judgment that human life is worth living, or rather can and ought to be made worth living, ... underlies all intellectual effort; it is the a priori of social theory, and its rejection (which is perfectly logical) rejects theory itself.

Herbert Marcuse

The validity of mathematical propositions is independent of the actual world-the world of existing subject-matters-is logically prior to it, and would remain unaffected were it to vanish from being. Mathematical propositions, if true, are eternal verities.

Cassius Jackson Keyser

Whether arrived at through reason or revelation, natural law is the highest law known to man. It is anchored in the very existential nature of man and is therefore a priori just.

Ilana Mercer

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.