ry psychology" is the only valid
psychology, is as well founded as the claim would be that only a
"literary physics" is valid. Mathematical physics gives us no more a
picture of the actual physical universe than Spinoza's psychology gives
us a picture of the mental and emotional life of an actual human being.
But the failure of these sciences to give us a picture of the living
world in no way invalidates their truth, or deprives them of their
utility.

Consider, as an example, Spinoza's psychological law freely expressed in
the dictum that Paul's idea of Peter tells us more about Paul than about
Peter. This conclusion follows strictly from fundamental principles of
Spinoza's abstract, dialectical psychology; but its truth or its
practical applicability is because of that not in the least impaired.
Indeed, because of its dialectical form its range of meaning is greatly
increased. Spinoza's dictum applies to what William James called the
"psychologist's fallacy." It also applies to what John Ruskin called the
"pathetic fallacy." Again, it applies to the fallacy Franz Boas exposed
and which he may justly have called the "anthropologist's fallacy." And
it applies also to what one may, with a great deal of benefit, dub the
"ethicist's fallacy." For the very same constitutional weakness of man
to identify confusedly his own nature with that of the object he is
contemplating or studying, is most flagrantly and painfully evident in
the fields of theoretical and practical ethics. The "ethicist's fallacy"
is the source of all absolutism in theory, and all intolerance in
practice.

All four fallacies just enumerated come under Spinoza's dictum as
special cases come under a general law. And these four are by no means
the only instances of the common habit of mind. From no field of human
endeavor is the mischief-working fallacy ever absent. We find it lodged
in the judge's decision, the propagandist's program, the historian's
record, the philosopher's system. In the field of metaphysical poetry it
has recently been identified by Santayana as "normal madness." In its
milder forms, the fallacy is now known by every one as the "personal
equation"; in its pronounced, abnormal manifestations it is known by the
psychoanalysts as "transference." It is a Protean fallacy woven into the
emotional texture of the human mind. Nothing, for it, is sacred enough
to be inviolate. For Spinoza discovered it sanctimoniously enshrined
even in the Sacr