Full Idea
Utilitarian thinking does not replace or compete with the moral law, but guides us when the moral law is silent and only sympathy speaks.
Gist of Idea
Utilitarianism merely guides us (by means of sympathy) when the moral law is silent
Source
Roger Scruton (Animal Rights and Wrongs [1996], p.63)
Book Reference
Scruton,Roger: 'Animal Rights and Wrongs' [Demos 1996], p.63
A Reaction
If the moral law is silent, it is not quite clear why we should follow sympathy rather than contempt. There is the well-known danger here of the moral law turning out to lack content.