226 Aristotle and his school
and of perception, since it is the matter of the body, and its influence varies
according to its being hot, cold, thin, thick, troubled or pure.
In these two passages, the influence of blood on intelligence is closely
linked with its influence on perception, and this again suggests that what
makes for greater intelligence is a better, that is, swifter, more accurate,
supply of perceptions for the intellect to halt upon. Aristotle’s remarks here
seem to refer tostructuraldifferences existing between different species of
animals, but there is no reason to doubt whether similarincidental,or
individual, variations in the state of the blood may make for incidental,
or individual, variations in intellectual performances.^70 Nor is there any
reason to believe that Aristotle is only referring to animals and not to man:
his remarks on the importance of the blood in the process of dreaming, for
example, indicate that also in human cognition the quality of the blood
is an important factor.^71 Again, this is of considerable importance to the
question whether Aristotle believed in animal intelligence: there is nothing
in these two passages to suggest that Aristotle is not referring toreally
intellectual activities of animals, but only to something analogous; on the
contrary, there is every reason to believe that similar variations in the state
of the blood affect human intelligence just as well as animal intellectual
capacities.
The most remarkable passage in this respect isDe an. 421 a 22 ff., which
suggests that there is a direct connection between degrees of softness of the
flesh and degrees of intelligence in human beings.^72 Aristotle deals with
the sense of smell, and he remarks that man has a very weak, unarticulated
sense of smell in comparison with many other animals: he is only capable
of labelling smells as pleasant or unpleasant. Similarly, he says, animals
with hard eyes ( #! ) do not have an accurate sense for seeing
a variety of colours. The situation is slightly better with taste, he says, for
man’s sense of taste is more accurate than his sense of smell, because taste
is a form of touch, and as regards touch man is the most accurate of all
animals.^73 He then continues:
(^70) See Kullmann ( 1982 ) 229 : ‘Es kommt freilich Aristoteles in 2. 4 vor allem darauf an, die physiologische
Bedeutung der beiden Bestandteile des Blutes hervorzuheben. Ihr jeweiliger Anteil ist nach seiner
Meinung von Tierart zu Tierart (und wohl auch von Individuum zu Individuum) verschieden.’
(^71) SeeInsomn. 461 a 25 ;b 11 ff.
(^72) The passage seems to be a sort of embarrassment to most interpreters, for it is hardly ever commented
upon. Freeland ( 1992 ) 234 says that ‘this should be taken with a grain of salt because Aristotle offers
several alternative explanations for human “superior intelligence” ’. However, Freeland does not
consider how these ‘alternative explanations’ are interrelated in Aristotle’s physiology, and of the
instances she cites onlyPart. an. 4. 10 is comparable to (and fully consistent with) the one here.
(^73) Cf.Hist. an. 494 b 17 ;Part. an. 660 a 12.