Because they're so intangible (and admittedly likely b/c I was younger!), I never used to consider attention, focus, and emotional regulation to be finite resources. Now that I do see them as finite, it's made me reconsider my approach to life. I see this as intimately tied to your post, and I like to interpret it as a bit of an analytical tradeoff. As you said, life will always present the unexpected, and what matters is our mind. We can choose to expend our energy foolishly attempting to adapt the territory to the map, or we can use our energy to update our map and thereby our view of reality. If we have to expend energy either way, it's a lot more effective to change our map, and it only costs letting go of our ego a bit. :)