Handbook of the History of Logic: - Fordham University Faculty

Logic and Theories of Meaning . . . 359
Compendium studii theologiae (1292), 58 his last, uncompleted, work. Especially
the last two treatises justify a treatment of Roger Bacon’s semantics in a chapter
on logic and theories of meaning in the late 13th century.
Signification is usually treated as a property of words or concepts. Bacon,
however, places the signification of words in a broader context of a theory of
signs. In De signis as well as in the Compendium 59 Bacon gives a classification of
signs. In the Compendium he claims that it is original, although he admits that
Augustine has a similar classification in De doctrina christiana. 60 A sign, he says
in De signis, is “that which once presented to a sense faculty or intellect designates
something to that intellect.” 61 This definition is similar to Augustine’s except for
the fact that Bacon’s definition allows for the case where something imperceptible
by a sensory faculty is a sign, whereas Augustine’s definition refers to sensible
signs only: “For a sign is a thing which of itself makes something other come into
thought beside the impression it makes upon the senses.” Bacon defends his choice
for a broader notion by referring to Aristotle who says that passions of the soul
(mental presentations) are signs of the things outside the mind. 62
According to Bacon, a sign is either (1) natural or (2) given by a living being
(data ab anima). (1) Natural signs occur in various modes, depending on the kind
of relationship between sign and significate. For example, in the (1.1) inference
‘she has milk; therefore she has given birth’, there is a (1.1.1) necessary relationship
between sign (having milk) and significate (having given birth). Likewise, dawn is
a natural sign of imminent sunrise through necessary inference. In other cases, for
example in ‘the ground is wet; therefore it has rained’ there is a (1.1.2) probable
relationship between sign and significate. In yet another sense, a footprint in the
snow is also a natural sign: it signifies the person whose it is. 63 This kind of sign
is (1.2) an expression of likeness. In this mode all artefacts are signs of art in the
mind of the artist.
(2) Signs that are given by living creatures (data ab anima) are divided into
two sub-modes: they can signify (2.1) naturally, e.g. in the sense that crying is a
sign of grief, but they can also signify (2.2) conventionally (ad placitum, litt.: at
pleasure), as is the case with spoken and written words, gestures of the deaf and
signs of monks. Other examples we could think of are traffic signs and the signs
of the conductor of an orchestra. This completes Bacon’s division of signs in the
first chapter of the Compendium.
Bacon is aware of the equivocity of the term ‘natural’ in his classification. The
first sense is related to ‘nature’ as opposed to ‘intellect’. Bacon refers to Aristotle’s
Physics for this distinction. 64 In the second sense, ‘natural’ means ‘arising from the
58Edited and translated by Thomas Maloney [1988]. See for more information about Roger
Bacon’s life and works Maloney’s introduction to this work.
59Compendium [25].
60Rosier [1997, p. 94] argues that this originality claim is improbable.
61De signis (2), ed. Fredborg et al., p. 82
62Peri hermeneias, 16a3-8.
63See for the sources of these examples: Marmo [1997, p. 145 ff].
64 De signis (12).