1 The Birth of Science - MSRI

162 6. The Hellenistic Scientific Method
Whereas with ordinary language one can talk reasonably only about
existing objects and observable phenomena, the hypothetico-deductive
method allows one to deduce from the “hypotheses” properties of objects
and phenomena that are virtually possible, but not yet in existence.
Science thus provides a formidable tool for technical design. Obviously
empirical tests remain essential, because one can never be sure of having
included among the “hypotheses” all the data relevant to one’s purpose.
A discussion about the relationship in Greek civilization between episteme
(, meaning “science”) and techne (, meaning “art, craft,
technique”) would require many pages, if nothing else because of the
amount of ink that Plato and Aristotle devoted to the subject. But the close
ties between the two in Hellenistic times are completely obvious. Several
of the subjects that for us are sciences are named after a Greek techne:
thus mechanics was originally , the art of building ma- page 208
chines. Even very specific areas of techne, such as making mirrors or theater
backdrops, gave rise to particular “sciences” (in this case catoptrics
and scenography, which Geminus calls subdisciplines of optics 44 ).
In some cases (optics, for instance) the name of a science arises in Greek
as an adjective that can be construed with either noun, episteme or techne.
This usage of course does not efface the difference in meaning between the
two nouns but it underscores the close relationship between the scientific
organization of certain disciplines and their origin in and application to a
particular techne.
Sextus Empiricus, in the part of his work called Against the rhetoricians,
refutes the widespread opinion that rhetoric is the art (techne) or science
(episteme) of discourse. For this purpose he transmits the following definition
of techne:
Every techne is a system of acquisitions of knowledge exercised together
in connection with some useful purpose in life. 45
This Stoic definition is reported with little variation by several authors 46
(and gave Lucian a pretext for writing an amusing satirical piece, making
the point that, on this basis, being a moocher or sponger is also a techne 47 ).
Another passage of Sextus Empiricus is also worth quoting:
Every existing techne and episteme is mastered though the works
() produced by that techne or episteme and associated with it. 48
44 Geminus, in [Heron: OO], vol. IV, 104, 9–12.
45 Sextus Empiricus, Adversus mathematicos, II, 10.
46 The versions that have come down to us are cataloged in [SVF], II, 93 to 97.
47 Lucian, De parasito, sive artem esse parasiticam.
48 Sextus Empiricus, Adversus dogmaticos, V, 188.
Revision: 1.7 Date: 2002/09/14 23:17:37