Empiricist

[em-pir-uh-siz-uh m] /ɛmˈpɪr əˌsɪz əm/

noun
1.
method or practice.
2.
Philosophy. the doctrine that all knowledge is derived from sense experience.
Compare (def 2).
3.
undue reliance upon experience, as in medicine; quackery.
4.
an conclusion.
/ɛmˈpɪrɪˌsɪzəm/
noun
1.
(philosophy) the doctrine that all knowledge of matters of fact derives from experience and that the mind is not furnished with a set of concepts in advance of experience Compare intuitionism, rationalism
2.
the use of empirical methods
3.
medical quackery; charlatanism
n.

c.1700, from empiric + -ist.
n.

1650s, in the medical sense, from empiric + -ism. General sense is from 1796.

Were I obliged to give a short name to the attitude in question, I should call it that of radical empiricism, in spite of the fact that such brief nicknames are nowhere more misleading than in philosophy. I say ’empiricism’ because it is contented to regard its most assured conclusions concerning matters of fact as hypotheses liable to modification in the course of future experience; and I say ‘radical,’ because it treats the doctrine of monism itself as an hypothesis, and, unlike so much of the half way empiricism that is current under the name of positivism or agnosticism or scientific naturalism, it does not dogmatically affirm monism as something with which all experience has got to square. The difference between monism and pluralism is perhaps the most pregnant of all the differences in philosophy. [William James, preface to “The Sentiment of Rationality” in “The Will to Believe and Other Essays in Popular Philosophy,” 1897]

empiricism em·pir·i·cism (ěm-pēr’ĭ-sĭz’əm)
n.

em·pir’i·cist n.