[mrec]

Back when I read about this stuff I had the exact opposite reaction - Occam's Razor seemed to favour Many-Worlds.

Given direct experience of one universe, I think it's more ontologically conservative to introduce multiple universes than it is to introduce a whole new unprecedented category of cats that are simultaneously dead and alive.

Very loose analogy: if I see a mouse in front of me and simultaneously hear a squeak behind me, I'd probably assume two mice rather than one mouse which has learned ventriloquism.

[osullivj]

Interesting. Occam's Razor says "don't multiply entities beyond need", not "don't multiply types of entities beyond need". Of course, you could argue that types are entities too. So many worlds minimizes entity types at the expense of total entity count.

[TeMPOraL]

"Number of entities" is probably best understood through Kolmogorov complexity. So two regular mice, or million regular mice aren't much more complex than one regular mouse. But having one regular mouse and one "special" mouse is more complex all of that.

[mrec]

Right.

Which makes it mildly ironic that John Wheeler, a leading early proponent of many-worlds, also proposed the one-electron universe...

[1] https://en.wikipedia.org/wiki/One-electron_universe