Full Idea
Men necessarily always agree with one another in so far as they live according to the guidance of reason.
Gist of Idea
In so far as men live according to reason, they will agree with one another
Source
Baruch de Spinoza (The Ethics [1675], IV Pr 35)
Book Reference
Spinoza,Benedict de: 'Ethics', ed/tr. White,WH/Stirling,AH [Wordsworth 2001], p.186
A Reaction
I think this was my earliest motivation for getting interested in philosophy. Oddly, the Socratic tradition of philosophy is to challenge and criticise, but the aim is agreement. I sort of believe this idea, despite its wild idealism.
Related Idea
Idea 12324 Consensus is the enemy of thought [Badiou]