On the whole I'm in favor of these alternatives. As a Christian it seems disrespectful and unloving towards other, non-Christian folks to simply expect them to adopt our way of looking at things. If one does not accept Jesus as Lord, then it is a falsehood for them to refer to this as the year of "our" Lord, and expecting them to do so feels rather imperialistic and arrogant. However, the irony, in my opinion, is that the designation "Common Era" doesn't actually solve the problem. It's still imperialistic to refer to the past 2000 years as a "common era" for anyone who is not actually a Christian. It's not shared in common by Muslims, for instance, or Jews, Buddhists, Hindus, Taoists, animists, etc.
Personally I think it would be more accurate and least offensive for CE and BCE to simply refer to "the Christian Era" and "Before the Christian Era". After all, everyone already knows what is being referred to, regardless of what you call it. And the term "Christian Era" simply names it for what it is without implying that non-Christians have to necessarily identify themselves within it if they don't want to (after all, many other cultures and religions - Islam, Hinduism, China, Judaism - have their own way of counting the years). It wouldn't require a confession of faith like AD does, nor would it mean falsely claiming that all people hold this system in "common", when in fact many have been forced to adopt it as a result of Western imperialism, or simply out of convenience/necessity.
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