Full Idea
What is good is the same as what is beautiful.
Clarification
'Beauty' is the Greek word 'kalos', which also translates as 'fine'
Gist of Idea
Beauty and goodness are the same
Source
Plato (The Symposium [c.384 BCE], 201c)
Book Reference
Plato: 'The Symposium', ed/tr. Hamilton,W [Penguin 1951], p.78