Why eating more chocolate might be better for your diet

In The Big Think Book, Cave mentions the puzzle of Sandy thinking at the beach and concluding that there is definitely more than one thousand grains of sand. She then reasons that she can't tell the difference between one thousand grains of sand and one thousand and one grains of sand. So she concludes that there must also be more than one thousand and one grains of sand.  That is, if she is confident that there is more than one thousand grains of sand on the beach, and she can't tell the difference between one thousand grains of sand, and one thousand and one grains of sand (without counting, of course), then there must be more than one thousand and one grains of sand.

But using this reasoning, she follows on and says that she can't tell the difference between one thousand and one grains of sand and one thousand and two grains of sand and concludes that there must also be more than one thousand and two grains of sand. You can see where this is heading, and going up one grain at a time she would get to billions and hundreds of billions.

Now I'm not going into the philosophical side of this (read the book yourselves), but the logic is that we should be able to tell the difference between one thousand grains of sand and two thousand grains of sand, correct?

We should then be able to use this to deal with other problems in life. For example, when we say 1 piece of chocolate won't affect our overall diet, and using the reasoning of the grains of sand, we end up eating 6 pieces (or the whole bar, because who stops at 6?). But if, and only if, we've convinced ourselves that we're going to eat the chocolate, maybe we're better off eating 3 pieces instead. That way we can more easily rationalise its effect on our diet and prevent ourselves from eating 3 more. So we might be inclined to think that 1 piece is better than 3, however if that 1 piece leads us to eat 5 more (one at a time) then we're better off eating 3 pieces at once.

This can (and is) applied in many other problems of similar nature, and the situation also applies in reverse. For example, breaking down a big problem into a group of smaller problems, and tackling them one at a time makes them much more achievable. Or "taking it one step at a time" as they say.