In my last post I discussed Steven Johnson’s book How We Got to Now: Six Innovations That Made the Modern World, and I couldn’t resist another post about it. It’s such a cool book, if you haven’t read it.

In his chapter called “Glass,” Johnson describes how in the early fifteenth century, glassmakers in Murano figured out a way to combine their clear glass with an amalgam of tin and mercury to make a shiny, reflective surface: the mirror. Before mirrors were invented, few people had ever seen an accurate reflection of themselves. And with that advancement, another innovation co-evolved: self-portraits. Before 1400, Johnson points out, there were virtually none. But with the invention of mirrors, Renaissance artists suddenly began painting themselves, because for the first time, they could accurately capture the features of their own faces. Rembrandt painted forty self-portraits.

Here’s just a sampling:

Taddeo di Bartolo, 1401

Raphael, 1506

Tintoretto, 1547

Artemesia, 1615

Two of Rembrandt’s 40 selfies