thing with which all experience has got to square" (pp.
vii-viii). An 'empiricism' of this description is a "philosophic
attitude" or temper of mind rather than a doctrine, and characterizes
all of Professor James's writings. It is set forth in Essay XII of the
present volume.

In a narrower sense, 'empiricism' is the method of resorting to
_particular experiences_ for the solution of philosophical problems.
Rationalists are the men of principles, empiricists the men of facts.
(_Some Problems of Philosophy_, p. 35; cf. also, _ibid._, p. 44; and
_Pragmatism_, pp. 9, 51.) Or, "since principles are universals, and
facts are particulars, perhaps the best way of characterizing the two
tendencies is to say that rationalist thinking proceeds most willingly
by going from wholes to parts, while empiricist thinking proceeds by
going from parts to wholes." (_Some Problems of Philosophy_, p. 35; cf.
also _ibid._, p. 98; and _A Pluralistic Universe_, p. 7.) Again,
empiricism "remands us to sensation." (_Op. cit._, p. 264.) The
"empiricist view" insists that, "as reality is created temporally day by
day, concepts ... can never fitly supersede perception.... The deeper
features of reality are found only in perceptual experience." (_Some
Problems of Philosophy_, pp. 100, 97.) Empiricism in this sense is as
yet characteristic of Professor James's philosophy _as a whole_. It is
not the distinctive and independent doctrine set forth in the present
book.

The only summary of 'radical empiricism' in this last and narrowest
sense appears in the Preface to _The Meaning of Truth_ (pp. xii-xiii);
and it must be reprinted here as the key to the text that follows.[1]

"Radical empiricism consists (1) first of a postulate, (2) next of a
statement of fact, (3) and finally of a generalized conclusion."

(1) "The postulate is that _the only things that shall be debatable
among philosophers shall be things definable in terms drawn from
experience_. (Things of an unexperienceable nature may exist ad libitum,
but they form no part of the material for philosophic debate.)" This is
"the principle of pure experience" as "a methodical postulate." (Cf.
below, pp. 159, 241.) This postulate corresponds to the notion which the
author repeatedly attributes to Shadworth Hodgson, the notion "that
realities are only what they are 'known as.'" (_Pragmatism_, p. 50;
_Varieties of Religious Experience_, p. 443; _The Meaning of Truth_, pp.
43, 118.) In this sense '