In my previous post about scientizing magic, one of the commentators inferred that evidence regarding magic and specifically spiritual entities was anecdotal and as such is not verifiable data. I disagree with that claim. Any magical working, including working with spiritual entities, involves a process. That process can be replicated by other people, which means it can be tested and verified by other people. Even putting that aside, if there are multiple anecdotal sources its rather cavalier to dismiss that evidence as unverifiable and unprovable, simply because that evidence doesn't fall into the scientific process. As is, open any book on magic and you will find that there are processes that can be replicated by other people, and as such results that can be verified by multiple people, if they choose to do so. As such, claiming that magic is only anecdotal data is a bit fuzzy, especially if other people can replicate your process and verify whether it works.
Magic isn't science, but magical practices can be verified by being tested. Obviously people wouldn't practice magic if they weren't able to get something out of it, but they also wouldn't be able to share their processes and practices if magic was only anecdotal. There would be no way to verify that magic worked if there weren't processes that could be replicated by other people.