Random observations on the intersection of science and art, from the National Gallery of Art in Washington, D.C.

1. If you want another great example of historical applications of the curse of knowledge (how much you take for granted that everyone knew, when in fact only modern people know), you'd do well to consider the painting 'Joshua commanding the sun to stand still upon Gibeon', by John Martin. It's a wonderful painting:

(Photo credit from the blog 'writing the city', which has an interesting writeup about the painting here)

But I want to focus on a small section of the painting near the storm cloud, which looks like this:

What's that diagonal scratch coming down the mountain? Did someone drop a knife on the painting?

No, my friends. That is the artist's depiction of lightning.

Which, to a modern reader, looks absurdly crude alongside everything else in the painting. Bolt lightning looks more like this:

(image credit)

So how did John Martin get it so badly wrong?

Well, think about it. How do you know what lightning looks like? Answer: because professional photographers using extremely high speed shutters are able to capture precise images of it, which you now take for granted.

If you were alive in 1816, where would your image of lightning come from? Answer: the quarter of a second flash in the sky that you saw maybe a couple of times in your life. Which, from your hazy recollection, probably looked like the line above.

It's amazing how much knowledge you take for granted.

2. Georges Seurat painted in a style called pointillism. In it, lots of tiny coloured points are placed next to each other to create the image of different colours when viewed from a distance. The National Gallery of Art example is called 'The Lighthouse:

(image credit)

What's amazing is that Seurat managed to figure out a primitive version of the RGB pixel displays that you're reading this on. The modern screens we look at are extreme forms of Seurat's pointillism - instead of lots of colours making up the points, we have only three, and instead of the points being large enough to see up close, they're so small that you're not meant to notice them. If you looked at TV screens back from the 80s up really close, you'd get to see the different colours.