There's been a lot of discussion about that incest question, but I don't think anyone's come out and said whether they think the scenario represents a moral transgression. I wonder what folks here think of the scenario. In fact, let's consider three scenarios:

• the scenario as stated, with outcome specified (ETA: that is, we know for certain that no harm occurred), under the (default) assumption that these siblings were raised together;
• the scenario with the outcome not specified, but these two have researched the question and, rightly or wrongly, have come to the conclusion that they are not more at risk than any non-sibling pairing; default assumption about raising;
• as above, but the siblings only met as adults.

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