The ancients did not distinguish between being
alive
and having a soul, which was conceived in various ways
as
something that organizes and controls the body.
Lacking optical
instruments, they had no concept of
the living cell, nor did they think of
flesh or wood as
possibly different from the constituents of nonliving
things. Life was given by the soul, both in animals and
in plants. Biology,
as the study of the living, is a modern
concept; when we speak of ancient
biology, we mean
the study of the ensouled. At the same time, the differ-
ence between living and nonliving
things was less
marked, because the ancients tended to assume that
all
matter possesses power and mobility and is quasi-
alive (the assumption that the material world is alive
is known
as “hylozoism”).
The early biological conceptions seem to originate
in pre-philosophical
reflection upon everyday experi-
ence. A
great deal of data was available concerning
husbandry, stockbreeding,
hunting, nutrition, medicine
and poisons, childbirth and dying, to which
was added
special information from Persian game reserves, from
the
wild animals of India, Egypt, and Libya, from the
Babylonian gardens where
the fertilization of fig and
palm was practiced, from augury and sacrifices, and
from ritual
crafts like root-cutting for drugs. From this
variety of data there arose
certain common ideas which
can be conveniently grouped under the topics of
the
four elements (Earth, Air, Fire, Water), the mysterious
extra
element (aether), heredity, species, classification,
and teleology. But
these ideas did not acquire precision
until philosophical argument came to
sharpen them.
Agriculture and medicine were conducted by tradi-
tional rule of thumb. It was the early
philosophers who
used these data to illustrate and justify their own cos-
mological arguments, and thereby evolved
biological
theories which were then taken over by the agricultural
and
medical writers (especially the Hippocratics). The
theoretical influence
therefore ran mostly from philos-
ophy to
biology rather than the other way. Zoology
and botany were not separated
from cosmology until
Aristotle departmentalized the sciences; and even
he
did not set up autonomous principles in biology, but
applied a
conceptual framework from his general phi-
losophy. The earlier biological theories therefore need
to be
understood in the context of larger physical
theories. Inevitably Greek
philosophy is the best place
to study these ideas. Not that the other
ancient civili-
zations lacked biological
speculation; but we do not
find there any major biological idea that does
not also
appear in the richer and fuller Greek discussions.