physics question

While on a moving ship, if a magus casts levitate on themself (or someone else on the same deck), according to ME physics do they levitate relative to the ship, or to the ocean ie the ship leaves them behind?

My gut instinct is they are levitating over the ship, thus they'd move with the ship.

Imagine if we went further and did factor in the rotation of the earth, or the movement of the universe. That would get dangerous very quickly.....


Take a look at A&A p.16ff Astronomy, or look up the Ptolemaic Model elsewhere.

No, the Earth with Mythic Europe on it does not rotate or move through the universe. The ship moves - also leaving T: Boundary spells behind (see e,g. LoH p.123 box A Note on Boundary Effects).

The levitating magus better be thrown a rope from the moving ship and hold onto it, or he is subject to the winds at sea first and might be left behind by the ship too.
See for this Aristotle's theory of motion in its medieval context.

I was just messing about. I believe AM is in the era where the Sun and moon are called planets. In AM, the Earth is literally the centre of the universe.

I hadn't thought about the wind. Definitely a problem. A calm day on a lake might be OK....

The moving ship would then still leave the levitating magus behind, as soon as the Philoponan 'impetus' has expired.

Could the maintenance of the spell be considered to be causing an ongoing impetus?

Rise of the Feathery Body - the ArM5 'levitate' - "allows the target to float vertically" only. Would it allow also horizontal movement, maintaining the spell could also maintain an horizontal 'impetus'.