Ben Levi:
I have indeed read the chapter in Torah Chazal and Science where he discusses R’ Avraham ben Harambam. He points out that there is no extant manuscript that contains that specific part. This does not mean that it is a forgery. It means that we can’t say for sure that R’ Avraham ben Harambam actually held this. However, the point is that all the people who subsequently quoted it, obviously didn’t think it was “against the mesorah”. But if you’re still not happy let’s look at another source:
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