This runs the simulation from satja/life — a description of a life in Python whose loops terminate only because checking a condition costs a minute. Set the conditions, then watch one life happen. Click the chart to inspect a moment, use ‹ and › or the arrow keys to move through it, and the tabs to go from the whole span down to a single day.
The two lists behave as they do in the source. things_you_should_do has a
length of zero unless you happen to remember it, so it sits at eighteen per cent opacity
and lights only in the instants it is in view. things_you_should_never_do has
a length of zero unless you are tempted. Both are there the whole time.