If you can't tell us why Primacy of Consciousness is necessary for MWI, then we have no grounds for doubting MWI on the basis of your argument. It's like saying that X is a perpetual motion machine and therefore impossible, and then when asked in what way is X a perpetual motion machine, replying that it's implicitly a perpetual motion machine and you can't relate the exact details.
Eliezer Yudkowsky and Scott Aaronson - Percontations: Artificial Intelligence and Quantum Mechanics
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