Thor 2
Philosopher
A knot is quite similar to a mile so when you are in a boat travelling at 40 knots you have a comparison point with car speed.
A nautical mile is based on the circumference of the earth, and is equal to one minute of latitude at the equator.
A knot is a speed of one nautical mile per hour.
A nautical mile and a knot are not 'imperial' they are dictated by the circumference of the earth and the requirements of navigation.
Well said but you forgot to emphasise that a knot is a unit of speed whereas a mile is a unit of length.
I suspect Vixen's "mathematical mind" may be a little befuddled. Easy to understand how this comes about when you are struggling with imperial units. As an engineer, I embraced the metric system with enthusiasm and relief, when it came into use in Australia. This I did in spite of the fact I was educated with the imperial nonsense. What a jumbled mess it was.
As an example of this mess, in one subject we used the pound as a unit of mass and in another the slug. There was no uniformity even within the system of units.
We have our intransigents in Australia also. Many of these younger than I, still insist on talking in inches, feet and yards. I respond by specifying a distance in cubits, spans, and such.