Full Idea
There is hardly anything so absurd or so mischievous that it may not, by means of early sanctions and influence, be made to act on the human mind with all the influence of conscience.
Gist of Idea
With early training, any absurdity or evil may be given the power of conscience
Source
John Stuart Mill (Utilitarianism [1861], Ch.3)
Book Reference
Mill,John Stuart: 'Utilitarianism (including On Liberty etc)', ed/tr. Warnock,Mary [Fontana 1962], p.284
A Reaction
Like this! Think of all the people who have had weird upbringings, and end up feeling guilty about absurd things. Conscience just summarise upbringing and social conventions.