Width of a Road
Takeaway
Constraints can come from unusual places, and can outlive and outlast their historical relevancy.
Epistemtic status: Not sure how true this is, but rhetorically interesting
Do you know why cars are the width that they are?
Because that's the width of the roads!
Okay, why are roads the width that they are?
Because that's how big a carraige was!
And why are carriages that width?
Because that's the width of two horses!