Full Idea
A writer who says that there are no truths, or that all truth is 'merely relative', is asking you not to believe him. So don't.
Gist of Idea
Why should you believe someone who says there are no truths?
Source
Roger Scruton (Modern Philosophy:introduction and survey [1994], 1.1)
Book Reference
Scruton,Roger: 'Modern Philosophy: introduction and survey' [Sinclair-Stevenson 1994], p.6