510 MR. J. S. HUXLEY ON THE 
itself with a sense of ‘“ something accomplished, something 
done.”) 
This merely indicates the possible material mechanism ; of the 
actual, we know next to nothing. However, by comparing the 
actions of the birds with our own in circumstances as similar as 
ossible, we can deduce the bird’s emotions with much more pro- 
bability of accuracy than we can possibly have about their nervous 
processes: that is to say, we can interpret the facts psychologi- 
cally better than we can physiologically. I shall therefore (with- 
out begging any questions whatever) interpret processes of cause 
and effect in terms of mind whenever it suits my purpose so to 
do—which, as I just said, will be more often than not. 
Let us take the parallel from human affairs. Far be it from 
me to go into the matter with a heavy hand; let us merely 
look at a few familiar facts in an unfamiliar biological light. 
The “courtship-actions” of man are mostly predetermined by 
heredity : any young couple that you like to take will be pretty 
certain to ‘express their emotion” by holding each other’s hands, 
by putting their arms round each other’s waists, or by kissing 
each other; and of this last action kissing on the mouth is the 
‘highest development.” Let us merely notice that these actions 
are not perhaps exactly parallel with what we find in the Grebe— 
that they are altogether more fluid, less fixed, and that they are 
sometimes less self-exhausting and more excitatory in character: 
on the whole, however, they are not very different. Moreover, 
in thei case we know a great deal about the accompanying 
emotions, either from our own experience or from what others 
tell us. ‘To take only the most specialized form of human court- 
ship-actions, the kiss; although we know that it may act as an 
excitant (¢f. Dante’s famous lines on Paola and Fra ncesca) yet the 
accompanying emotion is in itself quite special, different from all 
others, and the emotional process is usually something an wnd fiir 
sich, expressing itself in the action, and exhausting itself in the 
process with a feeling of inevitability. In the memory, however 
it, leaves its trace, and as it were desires to repeat itself, but 
only when the emotional tension shall again have risen (think of 
Plato’s epigram to Agathon: or the lovers in Richard Feyerel ; 
or Romeo and Juliet). That will suffice to show what I mean by 
a self-exhausting expression of emotion. Such a process would 
be one that to the doer of it feels at the time almost inevitable 
though he can only do it at certain moments. At other times. 
determined by his general mental state (cf. section 10, record 1), 
the action, however pleasant to recollection, is not “ spon- 
taneously” possible, and if performed is forced or at least not 
fully pleasurable. When normally executed, the action is accom- 
panied by violent and pleasurable emotion, which usually dies 
down, or changes, into a quite different feeling, one of satisfaction 
meanwhile leaving its mark in the memory. Its recollection 
then acts as a partial stimulus, so that next time it is a little 
more easily performed. 
