Originally Posted by
Ascended
Well it kinda depends on what school of ethics you want to follow. Kant ethics would answer differently than utilitarian ethics yknow? By Kant "what if everyone did this?" standards, Clark likely doesn't have to share the secret until he and Lois are serious about their relationship and a life-long bond/marriage is the obvious destination in both their minds. By utilitarian "does the good outweigh the bad" standards....hell, Clark might not have to tell her at all, given the weight of his responsibilities.
But it'd be awfully hard to slice this in a way that leaves Clark being 100% ethical regardless of the philosophy you follow; that would require a level of honesty and openness super early on that, frankly, is a huge risk and not how we function in society.
The absolute latest in my mind? Before proposing, or if you really want to push it, directly afterwards. That's the *latest* he can wait and still be relatively ethical.
Clark is not required to share his deepest, most carefully guarded secrets with someone he's just started dating. We don't do that, Clark shouldn't be required to either. And this isn't a typical kind of secret, sharing this potentially puts Lois in a whole lot of danger so sharing it too early, with someone you might not be dating in a few weeks, is legit irresponsible.
Sharing the secret before they have sex doesn't seem necessary to me either. At this point in his life Clark knows that his biology doesn't pose a danger to his partners; he's had an active sex life and Lana, Lori, and whoever else were never negatively impacted by Clark being Kryptonian. This does raise the question of whether Lois should know her partner is an alien....but in the Super-verse this is essentially just a more fantastical version of "my ancestors were Scottish." We don't feel the need to share our family origins with the people we sleep with so I'm giving Clark a pass here. If the DCU, or Lois specifically, didn't take aliens and magic and all the rest in such stride this might be more of an issue (it would be in the real world) but the Super-verse's internal logic is different from our's. Hell, the Daily Planet has had aliens as interns; being from another world is not the huge, massive deal it would be in reality.
So I'd say that, once the couple are definitely looking long term and assuming a life-long relationship will come of it, where most people start sharing their deepest secrets, that's the time when Clark should open up. However, because this is Lois and she has such a history of chasing Superman, I'm tentatively willing to let Clark slide until immediately *after* he proposes. He wants to make sure it's *him* that Lois is marrying and that she doesn't say yes because it's Superman; that's arguably an ethical choice on his part as he's trying to ensure their union is built on *them* and not the cape. Depending on the details of the continuity that might be more or less of a consideration though, it depends on how the "triangle for two" plays out and how hot Lois was for Superman before beginning a relationship with Clark. As much as Lois has a right to know she's marrying an alien, Clark has a right to know that he's marrying someone who loves him for him and not because of his public persona.
*If* Clark waits until he's proposed, he cannot wait to share this secret though. He needs to share it immediately after she says yes; before they tell anyone about the engagement, certainly before they start making any wedding plans. It has to be "Will you?" "Yes!" "Cool! Now sit down, before I put this ring on your finger you gotta know something and it's a big deal."
Whether that's still ethical is a bit dodgy, but like I said, there's considerations and elements in play that mean Clark can't be 100% ethical regardless of his choices.