INTRODUCTION. 21 
soning faculty and the imagination innumerable materials, and to indivi- 
duals means of communication, which cause the whole species to participate 
in the experience of each individual, so that no bounds seem to be placed 
to the acquisition of knowledge—it is the distinguishing character of hu- 
man intelligence. 
Although, with respect to the intellectual faculties, the most perfect ani- 
mals are infinitely beneath man, it is certain that their intelligence per- 
forms operations of the same kind. They move in consequence of sensa- 
tions received, are susceptible of durable affections, and acquire by expe- 
rience a certain knowledge of things, by which they are governed inde- 
pendently of actual pain or pleasure, and by the simple foresight of con- 
sequences. When domesticated, they feel their subordination, know that 
the being who punishes them may refrain from so doing if he will, and, 
when sensible of having done wrong, or behold him angry, they assume a 
suppliant and deprecating air. In the society of man they become either 
corrupted or improved, and are susceptible of emulation and jealousy; they 
have among themselves a natural language, which, it is true, is merely the 
expression of their momentary sensations, but man teaches them to under- 
stand another, much more complicated, by which he makes known to them 
his will, and causes them to execute it. 
To sum up all, we perceive in the higher animals.a certain degree of rea- 
son, with all its consequences, good and bad, and which appears to be about 
the same as that of children ere they liave learned to speak. The lower 
we descend from man the weaker these faculties become, and at the bottom 
of the scale we find them reduced to signs (at times equivocal) of sensibi- 
lity, that is, to some few slight movements to escape from pain. Between 
these two extremes the degrees are infinite. 
In a great number of animals, however, there exists another kind of in- 
telligence, called instinct. This induces them to certain actions necessary 
to the preservation of the species, but very often altogether foreign to the 
apparent wants of the individual; often also very complicated, and which, 
if attributed to intelligence, would suppose a foresight and knowledge in 
the species that perform them, infinitely superior to what can possibly be 
granted. These actions, the result of instinct, are not the effect of imita- 
tion, for very frequently the individuals. who execute them have never seen 
them performed by others: they are not proportioned to ordinary intelli- 
gence, but become more singular, more wise, more disinterested, in propor- 
tion as the animals belong to less elevated classes, and in all the rest of 
their actions are more dull and stupid. They are so entirely the property 
of the species, that all its individuals perform them in the same way, with- 
out ever improving them a particle. 
The working bees, for instance, have always constructed very ingenious 
