“Someone has (I think quite condescendingly) just told me that “Multiverses are suggested by pure math.. They are not ‘made up’.”
(Obviously, the key word here is “suggested”. But in what sense might this be considered a true statement?)”
Math holds a special place in the heart of most Modernists or Materialists, because math is entirely unmaterial, unphysical, and yet seems to partake of pure truth. If you speak to a mathematician, he will undoubtedly tell you he is a Platonist, that Math is something you discover, not something you invent. So when a materialist wants to tell you that something is absolutely, unalterable true, he has no better place to go than Math. That is why your friend is invoking his most precious god when he says that “multiverses are suggested by pure math”. But is this true? Would Plato have believed in multiverses?
No! Because Plato believed in unity. If Math is the god that rules the realm of Truth, there could never be multiple realms. Especially multiple realms with different math! Plato would have been appalled at the jobs given to multiverses. It would be like hiring Plato to clean toilets. Historically, this “One Truth” has been so influential, that nearly all Platonists would say “God is simple, He doesn’t have any parts.” or “All truth is God’s truth” etc. Multiverses are an abomination to Plato, and frankly, to most Metaphysicists.