Rand was, is, and always will be a pedestrian thinker. Yes, let's agree that trade is the only basis for human relationship. Here's a trade: “You agree to take risk A, and I'll agree to take risk B." For example, childbirth vs. military service, a deal that has been made for centuries. Thus, one can AGREE to sacrifice. One must then ask with regard to any given proposed act of sacrifice not whether, standing alone, it is in one's self-interest but whether it is an obligation undertaken by virtue of a relationship based on a trade. If it is, then is completely consistent with Rand's "philosophy," as if it were worthy of the name.

I agree that Aristotle provides Rand no support. Objectivist ethics appear to be strictly deontic, where Aristotle's are aretaic. But I'm a materialist, by which I mean that I look at behaviors not reasons. I see altruism as a behavior that can be supported by Rand's "trade of risks" (even if she didn't, because. remember, she's a lightweight) or as an Aristotelian virtue. Cartesian and Polar coordinates, tomato, tomahto.