-NovEMBER 26, 1897.] 
The English-reading public is not a little in- 
debted to the Open Court Company for its ren- 
‘dering into English of some of the best foreign 
writers of our day. Mr. Williams’s careful 
translation of Mach’s ‘Analysis of Sensations’ is 
# particularly valuable contribution. 
In turning again to a work that has been be- 
fore the public some twelve years, it will be 
unnecessary to. take up anew the discussion of 
the particular problems treated. The part 
played by movement, either actually performed 
or merely ‘willed,’ in our perception of space 
(p. 60, ete.), by the mechanism of attention 
with its background of continuous bodily pro- 
cesses in our sense of time (p. 111, etc.)—the 
parts played by these factors have come to be 
well recognized items in our psychological 
stock-in-trade. Mach’s contributions to the 
subject remain historically interesting as early, 
clear and richly illustrated efforts to call atten- 
tion to these elements in our concepts of space 
and time. His attempt to reconstruct the psy- 
chology of tone, if it has not met with any such 
general acceptance, presents, nevertheless, a 
method of treatment that no tone-psychology 
can afford to pass over without notice. Since 
the fundamental concepts involved go beyond 
the special field of audition and serve to illus- 
trate an attitude toward the whole psychology 
of sensation, reference to them may be left for 
that connection. 
The present review may thus confine itself to 
a discussion of the points of broader interest 
for which Mach stands. Such a task in con- 
nection with the work before us is rendered 
pleasant by the author’s simplicity of style and 
limpid clearness of thought. It is rendered 
difficult, on the other hand, by the desultory 
plan of treatment that he has consciously 
adopted. For although we are assured in the 
original preface that the same problem has 
been kept in mind throughout, yet to justify 
such a statement one must consider the prob- 
lem to be a very general one, indeed. 
Mach paves the way to the more technical part 
of his discussion by sketching in a most skillful 
manner a view of science in general, of psychol- 
ogy as a particular science, of the problem of 
sensation as illuminated by these general consid- 
erations. It is this part of the discussion that 
SCLENCE. 
811 
appears to the reviewer to be the central inter- 
est of the work. One feels, too, that it lay 
nearest the heart of theauthor. It seems, then, 
to demand rather close attention. 
Having swept the decks of such ‘meta- 
physical’ concepts as ‘things-in-themselves,’ 
science starts with complexes of experience, 
partly permanent, partly changing (p. 2). 
Among the relatively permanent complexes 
are the ‘self’ and the various groups we call 
bodies. Their permanence is, however, only 
relative; the division between them not fixed. 
The changes to which they are subject furnish 
an instigation to that analysis by which they 
are disintegrated into ‘elements’ (p. 5). These 
elements, for economic purposes grouped to- 
gether under single names, separated into not 
very definite wholes, are, in the end, all alike 
‘sensations’ (pp. 10, 152). Thus ‘ the world con- 
sists only of our sensations’ (p. 10). 
Starting from this empirical ‘monistic’ stand- 
point, it is with the ‘connections’ of this small 
number of ultimate elements that science deals 
(p. 18). The fields of the various sciences are 
defined, not by the kinds of elements they con- 
sider, but by the kinds of connections they 
take into account. Thus, the ordinary division 
between mind and body and the separation of 
sciences dealing with each is, like any other 
distinction between particular sciences, purely 
a practical device. ‘‘That traditional gulf be- 
tween the physical and psychical research, ac- 
cordingly, exists only for the habitual stereo- 
typed method of observation’’ (p. 14). ‘‘ There 
is no rift between the psychical and the physical, 
no within and without, no sensation to which an 
outward, different thing corresponds. There is 
but one kind of elements, out of which the suppo- 
sititious within and without is formed—elements 
that are themselves within and without accord- 
ing to the light in which, for the time being, 
they are viewed’’ (p. 151). Thesame elements, 
viewed as connected in those groups that we 
call physical bodies, are objects of study for 
physics; when one of these physical bodies is 
regarded as an organism their connection is 
studied by physiology; when considered as a 
chain of mental events they offer the subject- 
matter for psychology (p. 153). Thus, all science 
is primarily an attempt to reproduce facts in 
