Essays in Radical Empiricism

Essays in Radical Empiricism by William James is a collection edited and published posthumously by his colleague and biographer Ralph Barton Perry in 1912.

Empiricism is a theory of knowledge that asserts that knowledge comes only or primarily from sensory experience. One of several views of epistemology, the study of human knowledge, along with rationalism, idealism, and historicism, empiricism emphasizes the role of experience and evidence, especially sensory perception, in the formation of ideas, over the notion of innate ideas or traditions; empiricists may argue however that traditions (or customs) arise due to relations of previous sense experiences.

Empiricism in the philosophy of science emphasizes evidence, especially as discovered in experiments. It is a fundamental part of the scientific method that all hypotheses and theories must be tested against observations of the natural world rather than resting solely on a priori reasoning, intuition, or revelation.

This book was assembled from ten out of a collection of twelve reprinted journal articles published from 1904–1905 which James had deposited in August, 1906, at the Harvard University Library and the Harvard Department of Philosophy for supplemental use by his students. Perry replaced two essays from the original list with two others, one of which didn't exist at the earlier time.

Because the book is a collection of essays written over a period of time, and ultimately not selected or collated by their author, it is not a systematic exposition of his thought even though Perry suggests otherwise in his preface. This circumstance, in addition to the evolution of James own philosophic stance, has contributed to a wide variance in understanding, misunderstanding, and critical opinion of radical empiricism.

After James' death, Ralph Perry thought it appropriate to assemble a book on radical empiricism, and mined James' work on the topic to come up with the essays in this book:

"Does Consciousness Exist?"
"A World of Pure Experience"
"The Thing and Its Relations"
"How Two Minds Can Know One Thing"
"The Place of Affectional Facts in a World of Pure Experience"
"The Experience of Activity"
"The Essence of Humanism"
"La Notion de Conscience"
"Is Radical Empiricism Solipsistic?
"Mr. Pitkin's Refutation of Radical Empiricism"
"A Reply to Mr. Pitkin"
"Humanism and Truth Once More"
"Absolutism and Empiricism"

The notion of tabula rasa ("clean slate" or "blank tablet") connotes a view of mind as an originally blank or empty recorder (Locke used the words "white paper") on which experience leaves marks. This denies that humans have innate ideas. The image dates back to Aristotle: What the mind (nous) thinks must be in it in the same sense as letters are on a tablet (grammateion) which bears no actual writing (grammenon); this is just what happens in the case of the mind. (Aristotle, On the Soul).

Aristotle's explanation of how this was possible, was not strictly empiricist in a modern sense, but rather based on his theory of potentiality and actuality, and experience of sense perceptions still requires the help of the active nous. These notions contrasted with Platonic notions of the human mind as an entity that pre-existed somewhere in the heavens, before being sent down to join a body on Earth (see Plato's Phaedo and Apology, as well as others). Aristotle was considered to give a more important position to sense perception than Plato, and commentators in the middle ages summarized one of his positions as "nihil in intellectu nisi prius fuerit in sensu" (Latin for "nothing in the intellect without first being in the senses").

During the middle ages Aristotle's theory of tabula rasa was developed by Islamic philosophers starting with Al Farabi, developing into an elaborate theory by Avicenna and demonstrated as a thought experiment by Ibn Tufail.