Re: Janeway's Decision to Kill Tuvix
Tuvix was unwilling to make the sacrifice Tuvok or Neelix would have willingly made to save his own life, had they been able to choose.
If he was really a composite of them then it stands to reason that he should have made the choice that they would have made, though I suppose we can't anticipate what he'd do if they'd disagree on how to approach a situation.
If his making a decision that they wouldn't make is evidence that he's not, strictly speaking, a composite of them, then the case for him being a unique being is strengthened.
Granted this wouldn't be the first time a Trek captain killed a possibly unique being.
It was the best of Trek, it was the worst of Trek...
"If I lean over, I leave myself open to wedgies, wet willies, or even the dreaded Rear Admiral!"