Species

The Medieval Bridge 35

held that universals existed solely in the understanding, or at least that is the nomi-
nalist position as later understood. Probably Roscelin did not assert this, but merely
rejected Realism, and Ockham’s version might be better called Conceptualism rather
than an outright denial of universals, as he did not deny that universals did not exist
as concepts.
The conception of species in this debate centered largely on the objects of knowl-
edge rather than on anything particularly biological. However, as evidenced in the
ninth century in John Scotus Eriugena’s (or Duns Scotus; 815–c. 877) De divisione
naturae (The division of nature), biological examples are used to illustrate the dis-
cussions.^8 These issues come to the fore again in late twentieth century philosophy
of biology under the banner of species-as-individuals.
Peter Abelard (or Abelaird; 1079–1142), perhaps the best of the philosophers
before the rediscovery and dissemination of Greek texts via the Arab translation
in the twelfth and thirteenth centuries, was inuenced by the nominalist claim, and
had studied under Roscelin. He convinced his lecturer William of Champeaux to
modify his Realist position, for example. In his Gloss on Porphyry, he asserted that
universals are names only, akin to proper nouns but applicable to many things rather
than one thing, based on a common likeness. The universal noun does not refer to a
thing that is universal, for only individuals exist. His views led to his being declared
heretical by later writers, including Bernard of Clairvaux.
For Abelard, species is a purely logical notion, and he says

... considering the nature of species in man, I nd at once from the nature of the spe-

cies the argument for proving animal.^9

That is, if you understand what sort a man is, then you know that the sort includes
the species Animal, just as Aristotle’s De anima asserted, and this is a logical truth.
William of Ockham (or Occam; c. 1300–1349) is perhaps the most enduringly
inuential of the medieval nominalists. For him, logical species are just a way to
recollect similar individuals already encountered, and a general term cannot be
abstracted from a single individual, but only a number of individuals encountered,
as he says in The Seven Quodlibita.^10 Hence to assert that something coming from a
distance is an animal, one must already have that concept by recollecting prior indi-
vidual animals. This demonstrates that the nominalist is attempting a “bottom-up”
form of classication, based on observed cases. Moreover, species, logical or oth-
erwise, are things which have the same “power,”^11 but concepts of them are of the
“second intention” (that is, are categorized by the mind):

... that concept is called a second intention which signies precisely intentions natu-

rally signicative, or which sort are genus, species, difference, and others of this sort

[i.e., heads of predicables] for as the concept of man is predicated of all men ..., so too

one common concept, which is the second intention, is predicated of rst intentions

(^8) Book IV [McKeon 1929, 10 7–141].
(^9) McKeon 1930, 211.
(^10) Quod. 1, ques. 13 [McKeon 1930, 365].
(^11) Quod. V, ques. 2.