Originally posted by Bosse de Nage
"Treat others the way you want to be treated".
"An' it harm none, do what thou wilt".
Are these imperatives identical?
My understanding is that the Wiccan rede is an outgrowth of Crowley's "Do What Thou Wilt Shall Be The Whole Of The Law." Gerald Gardner, the reviver of 20th century witchcraft in Europe, did study some of Crowley's teachings, as far as I know.
"Do What Thou Wilt" doesn't have anything to do with "do your own thing", it was intended as a statement pointing to the Higher Will, beyond the personal (ego-driven) will of personal agendas and attachments/aversions. The "Higher Will" is also the "natural will", or the "natural state", as the Tibetans call it, that arises as the mind is purified of delusion and distortion (purified via spiritual practices). That's the theory, anyway.
Crowley added on "Shall Be The Whole Of The Law" to indicate that once the mind is spiritually trained, then the Higher Will is seen to be the only real will; the personal, ego-driven will is revealed to be based on illusion, and therefore illusory itself (in the ultimate context). Another way of putting that is via the old Sufi expression, "Only God Is", or "only ultimate reality is". This doesn't mean that the ego-realm is unreal when in it, only that it is compared to the nature of a dream-world (and often a nightmare) that is woken up out of. Once awake we realize that our dream was "just a dream"; but when in it, the dream is real by the standards of the dreamer.
The Wiccan rede replaced "Shall Be The Whole Of The Law" with "an it harm none", which seems to be a result of Christian influence, possibly from Gardner's Christian roots, would be my guess, though that is a principle found in all major religions. Basically, the Wiccan rede is a milder expression of Crowley's "magickal maxim". I'm not actually sure however how well modern Wiccans understand Crowley's original ideas behind the saying.