J.—PSYCHOLOGY. 223 
physiognomist observes. The neuro-muscular tonus—the tightness 
around the eyelids, the firmness of the lips—is an index of the general 
state of health and vitality upon which a man’s intelligence and atten- 
tion so much depend. The changes of look and glance afford a clue, 
however indirect, to the range, the liveliness, and even the character 
of his interests. Above all, it is to be remembered, almost every human 
emotion has its instinctive facial expression, to which, by a sort of 
primitive sympathy, we ourselves as instinctively respond. The 
emotions (we shall see) are the foundations of character. And the 
emotional mood that predominates in a given person’s life tends, by the 
simple law of habit, to leave its natural expression stamped upon the 
countenance, contracting almost permanently the underlying muscles, 
and deepening the furrows and the finer lines upon the skin. Thus 
the bad-tempered bully comes to wear always a more or less angry 
scowl, and the anxious melancholic a worried look upon the brow.™ 
“In many’s look the false heart’s history 
Is writ, in moods, and frowns, and wrinkles strange.’ 
In the main, however, the gist of recent scientific work on connee- 
tions between body and mind has been, from a practical though not, 
from a theoretical standpoint, negative. Theories, such as that of 
Lombroso and his school—the notion of criminal, defective, neurotic, 
and supernormal types, each marked off from ordinary mankind by a 
specific combination of physical and mental traits—have been exploded 
by more careful statistical methods. The measurable correlations, 
though frequently positive, are almost always too slight to be trusted 
for the needs of diagnosis.'* Thus a man’s exterior is sometimes 
suggestive, but never conclusive. And so we reach the safe and central 
maxim of individual psychology of to-day: Judge mental functions by 
mental symptoms, not by physical. The worldly moralist agrees. ‘ Tl 
ne faut pas juger des hommes comme d’un tableau ou d’une vache; 
il y a un intérieur et un cceur qu’il faut toujours approfondir.’ '® 
2.—Mental Condition. 
I proceed now to what consequently becomes the essential duty of 
the practical psychologist—the direct examination of the mental state. 
The positive foundations for a practical psychology of individual 
differences have been laid in three broad generalisations, each the 
separate suggestion of recent experimental work. They consist in 
a trio of important distinctions, the distinction between intellectual 
and emotional characteristics, between inborn and acquired mental 
13 These deductions can be verified by the method of correlation, see Child 
Study, June 1919, ‘ Facial Expression as an Index of Mentality ’; also Langfeld, 
‘Judgments of Emotions from Facial Expression,’ J. Abn. Psych., xiii., 172) 
and Psych. Rev., xxv., 488. The general principle underlying ‘ whatever truth 
the so-called science of physiognomy may contain ’ is stated, as in the text, by 
Darwin, Expression of Emotions in Man and Animals, p. 388. 
sig Shakespeare, Sonnets, xciii. 
15 The labours of Karl Pearson and his students, following the methods of 
Galton, have been invaluable in this field. Goring’s study of The English 
Convict is a model for inquiries upon these and kindred problems. 
16 La Rochefoucauld, Mazximes Morales, ccexvii. 
1923 R 
