Routledge History of Philosophy Volume IV

RENAISSANCE AND SEVENTEENTH-CENTURY RATIONALISM 137
case, however, did the scholastics or rhetoricians consider induction as a logical
process for gaining knowledge. Francis Bacon was well aware of this tradition,
and so he calls ‘puerile’ (Nov. Org. I, 105: I, 205; IV, 97; cf. also I, 137; IV, 24)
the imperfect induction of the Schoolmen. That he did not care to mention the
inductio perfecta may mean that, like other theoreticians afterwards, he did not
consider it induction at all. 36 Be that as it may, a cursory perusal of Bacon’s
description of his own form of induction, and, above all, of the illustrations he
gives of its deployment and use in Novum Organum II, 11–12, 36, builds up a
strong case for deciding that Bacon’s employment of the term (even as of the
term ‘form’, as we shall see) is but a mark of his self-confessed terminological
conservatism (Nov. Org. II, 2), rather than a direct reference to a lexically wellestablished
notion.
The starting-point for the deployment of Bacon’s inductio is roughly similar to
that of previous inductiones (as described in contemporaneous textbooks of
philosophy and rhetoric). 37 Nevertheless, it covers a register of logical
procedures and is directed towards an aim —i.e. the discovery of Forms—that
separates it off from traditional acceptations of that term. As a matter of fact,
Bacon’s inductio belongs to the new-born movement of the ars inveniendi, and
perhaps we should understand the term inductio as an umbrella word of sorts
covering different steps and procedures. 38 For brevity, I shall call them (1) the
inductive, (2) the deductive and (3) the analogical steps.
Bacon never tired of stressing that before his great logical machine could be
put into use a vast collection or inventory of particulars should be made, building
up a ‘natural history’ (historia naturalis et experimentalis) on which the
investigator could firmly base himself before proceeding further. This notion of a
‘natural history’ found its finest hour with the members of the Royal Society, and
even Descartes wrote to Mersenne most approvingly about this Baconian project. 39
The notion, however, is somewhat circular in Bacon’s mind, for natural histories
worth their salt should contain a record of artificial things or of ‘effects’ (opera)
wrought by man, that is, ‘Nature in chains’ (I, 496ff.; III, 33ff.; IV, 253), and
also of what we would term today ‘theory-laden experiments’ or, in Bacon’s
colourful phrase, information resulting from ‘twisting the lion’s tail’: these are
called upon to show how Nature behaves under unforeseen or ‘unnatural’
circumstances. The artificialist twist that Bacon gave to his original notion was
not always well understood, and the full meaning of his concept of ‘experience’
became duly simplified as time went on and Bacon’s insight simply came to
mean ‘compilation’. 40
If, as L.Jonathan Cohen argues, all inductions can be divided into ampliative
and summative, 41 then Bacon’s concept is clearly a case of ampliative induction
by way of elimination. It is not the sheer number of instances that counts in
Baconian induction, but what we can term their ‘quality’. This is clearly
expressed by Bacon in the Novum Organum by isolating twenty-seven privileged
or ostensibly telling manifestations of the phenomenon under study (i.e. a natura
in Bacon’s terminology) which carry a special, sometimes decisive, weight in the