Full Idea
The good is beautiful.
Clarification
'Beauty' is the Greek word 'kalos', which also translates as 'fine'
Gist of Idea
The good is beautiful
Source
Plato (Lysis [c.400 BCE], 216d)
Book Reference
Plato: 'Early Socratic Dialogues', ed/tr. Saunders,Trevor J [Penguin 1987], p.150
A Reaction
also Timaeus 87c