Dome Cappella Chigi from inside, Santa Maria del Popol

on tessera(e)


The Chapelle Palantine, illuminated by sunlight and candles.

By Urban~commonswiki; used under a CC licence.


I wrote a piece recently for BotWatch that touched on this, but I wanted to give a brief explanation of why I use the word “tessera” when I talk about my bots.

A tessera is a single tile used in a mosaic; every tessera is suspended in mortar, and depending on where the mosaic’s viewer is standing and the lighting conditions, different tiles may be illuminated. Guy Gavriel Kay explains in Sailing to Sarantium:

“The curve and the height of a dome allow us the illusion of movement through changing light, my lord. Opportunities beyond price. It is the mosaicist’s natural place. His… haven. A painted fresco on a flat wall can do all a mosaic can, and-though many in my guild would call this heresy-it can do more at times. Nothing on Jad’s earth can do what a mosaicist can do on a dome if he sets the tesserae directly on the surface.”

a list of words from @thinkpiecebot

Some of @thinkpiecebot’s tesserae.

My bots have lots of words and phrases in them and they’re set in formulas, what the bot says is chosen pseudorandomly, just like the flicker of a candle may psuedorandomly “choose” different tesserae to illuminate, and how their flickering and winking will be different for people standing in different places.

In some ways, I’m creating the illusion of human thought where there isn’t any; which of my tesserae is “illuminated” depends on what the random number picker that puts bot tweets together happens to land on. Just like changing light creates the illusion of movement, the random numbers create the illusion of a mind behind what the bots post.

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