Forgive me if you already are familiar with this stuff. I think the coolest thing I’ve seen so far is Masaccio’s Holy Trinity, a fresco in the Basilica of Santa Maria Novella. In 1428 CE, it is the first time an artist used Brunelleschi’s concept of linear perspective to represent a 3-dimensional space in a 2-dimensional painting. In addition, the composition is a kind of a motif used in many paintings- Christ on the cross in front, God the Father behind (sometimes seated on a throne), and the Holy Spirit represented as a dove near Christ’s head (see the first two paintings below). In case you (like me) need some remedial art history, here are a couple of websites explaining how Brunelleschi developed the concept of linear perspective and how Masaccio used it in the Holy Trinity: https://smarthistory.org/masaccio-holy-trinity/ and https://www.khanacademy.org/humanities/renaissance-reformation/early-renaissance1/beginners-renaissance-florence/v/linear-perspective-brunelleschi-s-experiement
John and Susan's Excellent Adventure 