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2) Sometimes there are tradeoffs. This happens when you're on the "pareto frontier" -- the set of all options that aren't strictly dominated by any other. If you're in some convex space, this means you're on the boundary: something might have more A or more B, but not both.
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3) When you're on the pareto frontier, there is no free lunch. There are always tradeoffs. Sure, you could get something tastier, but it'll also be more expensive, or less healthy. For instance, pie tastes better than celery, but also it's less healthy.
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4) Sometimes there are not tradeoffs. This happens when you're _not_ on the pareto frontier. This means you're on the inside of the space, and you would be better off on the surface.
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5) For instance, maybe you're currently eating diamonds. As it turns out eating diamonds is less healthy, less tasty, and more expensive than pie. There are no tradeoffs here. Stop eating diamonds and start eating pie.
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