[Leonardo] liked rude boys who stole, rough diamonds, like Salai who came as an assistant at fifteen and stayed for life.And especially this:
In the 1430s a fourteen-year-old boy could be burnt at the stake for an act of sodomy - this would not happen in Florence again. Platonism confirmed that it was right and proper to love someone of your own sex - a more practical way of viewing sexuality than the church's blueprint of DON'Ts. The modern world received the message with open arms and Botticelli, Pontormo, Rosso, Michelangelo and Leonardo stepped from the shadows.
I know this is a long way from light and colour ... but is it? For Leonardo took the first step into light, and Newton, a notorious bachelor, followed him with Opticks. In this century Ludwig Wittgenstein wrote his Remarks on Colour. Colour seems to have a Queer bent!