Naming algorithms and the ghosts in Pac-Man

22.04, Monday 7 Sep 2020 Link to this post

How do we relate to the algorithm? Here’s one way…

Sproute is a navigation app that diversifies how you travel by offering a set of characters that get you to your destination in different ways.

For example maybe you want to avoid dark and unlit streets at night, or maybe you could go sightseeing on the way to your destination?

I met Breitenstein on one of my Wednesday calls. (I open my calendar for a few slots every week, for serendipity purposes. Wednesdays are now my favourite day. Rationale and booking link here.)

His prototype app, Sproute, is a replacement for the Google Maps routing system with a few different options, each embodied as a character:

  • Sightseer – who routes you via landmarks
  • Nightlight – who always takes you on well-lit streets
  • Commuter – who subtly changes up your route to work each time you travel.

Great write-up of the design process at the above link.


Here’s Chapter 4 of the Pac-Man Dossier (2009), an enormously in-depth guide to the original 1980 Pac-Man arcade game.

It turns out that the four ghosts embody four different pursuit algorithms and their descriptions in Japanese are poetic explanations of those strategies. I’m going to dump the details of all four here because I am forever trying to find this in my notes.

  • Blinky (red) moves towards Pac-Man’s current tile. In Japanese, oikake which means to run down or pursue.
  • Pinky (pink) heads tiles four ahead in the direction Pac-Man is moving. Japanese: machibuse: to perform an ambush.
  • Inky (turquoise) embodies logic to catch Pac-Man in a pincer movement with Blinky, initially by moving in the opposite direction. Kimagure: a fickle, moody, or uneven temper.
  • Clyde (orange) moves towards Pac-Man if within 8 tiles, no pursuit otherwise. Otoboke: pretending ignorance.

I think that when we don’t name the algorithm, it’s hard for us to imagine it could work any other way.

We imagine that the Google Maps algorithm must be the best way to get from A to B, because it’s the only way. Like nature.

(It’s telling that, when users get more expert, they do start naming algorithms. The SEO community has names for the various Google Searches over time.)

I don’t think we should anthropomorphise algorithms – if we say that the Facebook news feed algorithm (for example) has its own agenda, that implies it has agency, and that obfuscates the fact that it’s actual people at an actual company who made the decisions to have it work that way.

But names… names give us a way to have a public conversation about biases and consequences. Names let us imagine alternatives.