Familiarity may breed contempt in some areas of human behavior, but in the field of social ideas it is the touchstone of acceptability.
A thing is not proved just because no one has ever questioned it. What has never been gone into impartially has never been properly gone into. Hence scepticism is the first step toward truth. It must be applied generally, because it is the touchstone. - Denis Diderot
The touchstone of everything that can be concluded as a law for a people lies in the question whether the people could have imposed such a law on itself. - Immanuel Kant
There are some things we can never assign to oblivion, memories we can never rub away. They remain with us forever, like a touchstone. - Haruki Murakami
A child's hand in yours -- what tenderness and power it arouses. You are instantly the very touchstone of wisdom and strength.
The true spirit of delight, the exaltation, the sense of being more than Man, which is the touchstone of the highest excellence, is to be found in mathematics as surely as in poetry. - Bertrand Russell
Adversity is the touchstone of friendship. - French Proverb
My touchstone for following a line of wisdom is; ‘living the philosophy should bring freedom to the individual, and love, wisdom and compassion to society, to our relationships’. - Phil 'Philosofree' Cheney
In the 21st century men’s tits have not just rivalled but replaced women’s as the touchstone of ‘sexy’ in mainstream pop culture, even when the audience for them is other men. - Mark Simpson