Key Arguments

• Smith defines this duty as concerning 'those public institutions and those public works, which though they may be in the highest degree advantageous to a great society, are, however, of such a nature, that the profit could never repay the expense to any individual, or small number of individuals'.
• Because such works are not profit‑repaying at the individual level, 'it, therefore, cannot be expected that any individual, or small number of individuals, should erect or maintain' them, so the sovereign must assume responsibility.
• After works necessary 'for the defence of the society, and for the administration of justice,' the remaining works of this kind are 'chiefly for facilitating the commerce of the society, and those for promoting the instruction of the people,' which Smith explicitly places under this third duty.
• He further classifies institutions for instruction into 'those for the education of the youth, and those for the instruction of people of all ages,' indicating that the public role extends across the life course.

Source Quotes

Of the Expense of public Works and public Institutions. The third and last duty of the sovereign or commonwealth, is that of erecting and maintaining those public institutions and those public works, which though they may be in the highest degree advantageous to a great society, are, however, of such a nature, that the profit could never repay the expense to any individual, or small number of individuals; and which it, therefore, cannot be expected that any individual, or small number of individuals, should erect or maintain. The performance of this duty requires, too, very different degrees of expense in the different periods of society.

The performance of this duty requires, too, very different degrees of expense in the different periods of society. After the public institutions and public works necessary for the defence of the society, and for the administration of justice, both of which have already been mentioned, the other works and institutions of this kind are chiefly for facilitating the commerce of the society, and those for promoting the instruction of the people. The institutions for instruction are of two kinds: those for the education of the youth, and those for the instruction of people of all ages.

After the public institutions and public works necessary for the defence of the society, and for the administration of justice, both of which have already been mentioned, the other works and institutions of this kind are chiefly for facilitating the commerce of the society, and those for promoting the instruction of the people. The institutions for instruction are of two kinds: those for the education of the youth, and those for the instruction of people of all ages. The consideration of the manner in which the expense of those different sorts of public works and institutions may be most properly defrayed will divide this third part of the present chapter into three different articles.

Key Concepts

• The third and last duty of the sovereign or commonwealth, is that of erecting and maintaining those public institutions and those public works, which though they may be in the highest degree advantageous to a great society, are, however, of such a nature, that the profit could never repay the expense to any individual, or small number of individuals; and which it, therefore, cannot be expected that any individual, or small number of individuals, should erect or maintain.
• After the public institutions and public works necessary for the defence of the society, and for the administration of justice, both of which have already been mentioned, the other works and institutions of this kind are chiefly for facilitating the commerce of the society, and those for promoting the instruction of the people.
• The institutions for instruction are of two kinds: those for the education of the youth, and those for the instruction of people of all ages.

Context

Opening of Book V, Chapter I, Part III ('Of the Expense of public Works and public Institutions'), where Smith defines and scopes the sovereign’s third duty before subdividing the discussion into articles on commerce‑facilitating works and instruction.