I have never personally understood dualism very well, although it seems to run rampant in many corners of the pagan community. In my particular focus on fairies and fairylore I also see this dualism expressed in the idea that some people have that fairies are either good or bad, or in some views must be wholly good, or in others wholly bad. I tend to reject these concepts but I think its important to discuss why.
To begin let's start with what dualism is, so we're all on the same page, because there are several definitions. For our purposes here the meaning we are using is that of a worldview that divides things into the opposing groups of good and evil. In cosmology this is often expressed through the idea of powerful benevolent deity/deities in opposition to malevolent cthonic or entropic forces. The benevolent forces seek to preserve or improve the human world while the opposite forces seek to destroy it; that which seeks to preserve is labeled by humans as 'good' while that which seeks to destroy is called 'evil'.
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