The purpose of this dissertation is to provide an account of the influence and impact of David
Hume, Adam Smith and Thomas Reid's depiction of language on their characterisation of the
origin, communication, and development of moral sentiments. These thinkers were well aware that
none of the arts, sciences, or institutions of man could have developed without language.
Furthermore, language was recognised by them as essential for the transmission of knowledge from
one individual to another. As a result, it will be argued that discussions of language and language
use by Hume, Smith and Reid played an important role illustrating, substantiating and corroborating
their theories generally, and more specifically, lend insight into their conclusions regarding the
development of human sociability and morality. Utilising published works, as well as unpublished
personal and student notes, this thesis traces both the role of language in the construction of the
individual theories of Hume, Smith and Reid as well as the theoretical tensions which arose between
these philosophers relating to their characterisation of language and language use in relation to
man's formation of a conception of morality.
Theorising on the origin and implication of language held an important place in the European
Enlightenment generally, with some of the greatest thinkers of the period contributing to the debate.
As a result, this thesis will first engage in a brief overview of the major discussions of the nature and
origin of language and its relation to morals in the time leading up to the period in question, as well
as the contemporary debate. This section aims to provide a conceptual framework from which to
explore Hume, Smith and Reid's concurrence or divergence from the contemporary debate
regarding the relationship between man's use of language as the central tool of interpersonal
communication, and how this fact relates to man's conception of virtue and vice.
The thesis next turns its attention to the work of David Hume. Aiming to construct a
comprehensive analysis of Hume's scattered linguistic references, it will be argued that the
relevance of examining Hume's characterisation of language relates directly to his claim that it is
custom and convention, rather than autonomous reason or innate sentiment, which are principle
means of shaping man's social and moral character. As a result, references to language and
language use by Hume served as a significant tool in illustrating and substantiating his more general
theoretical claims regarding man's social and moral character.
Building upon the analysis of Hume, the thesis next turns its attention to an exploration of the
influence of such linguistic assumptions on the moral theory of Adam Smith. While agreeing with
many of Hume's interpretations as to the character of language, it is clear that Smith did not share
Hume's faith in the ability of linguistic convention to serve as a reliable medium of moral guidance.
Maintaining that Smith's The Theory ofMoral Sentiments and writings on rhetoric are at the centre
of his thinking on language and language use, we will investigate how his characterisation of
language is reflected in, and exercised influence upon, his conception of man's morality and
sociability. Perhaps the best example of the multifarious implications of language and language use
in the presentation of man's sociable and moral character amongst the theorists being discussed,
Smith's references to language and language play a significant supportive role in the substantiation
and dissemination of his theory.
To highlight the influence of linguistic analysis on the period's characterisation of morals, the
final stage of the thesis explores the efforts of Thomas Reid to present a countervailing theory of
morals from that of both Hume and Smith. Drawing upon Reid's published works, private notes,
and student lecture notes; the closing section examines Reid's utilisation of a very different
interpretation of the nature and role of language in his effort to challenge the forces of scepticism
and moral relativism.
