First, don't take my ruminations in this post to mean that I am going to become a profligate consumer of things because I no longer believe in scarcity. I've got a natural inclination to be frugal, and that includes use of resources on general principles.
I was looking at a friend's recirculating waterfall. It is very pretty, but I asked myself if it was a waste of electricity just to entertain us. The conventional answer would be yes. But then I realized that Nature does the same thing, using solar energy on the ocean and lakes to lift water up and then drop it to run down the streams, rivers, and waterfalls to the ocean. Thus I arrived at the central question of this post: Why do we consider certain things to be wasteful when done by man, but not when occurring in nature?
Another example is a mountain spring. Where I was last week there was a natural spring with good water. Of course it trickles out of the mountain continuously, and except for the small amount caught when a person is there, it runs down and into a river and down the mountain. Now if I were to run my pump to bring water out of the aquifer, and left my hose to run continuously into the nearest stream, most people would say I was wasting a tremendous amount of a precious resource. Again, one example is naturally occurring while the other is performed by man, but what is the difference in the net effect?
We can ask the question not only in cases where man uses a resource, but where he fails to capture it as well. Since Nature is using energy to lift water which is then running downhill, are we negligent in not capturing every bit of that energy which is being "wasted" in friction with the rocks? Should every waterfall be diverted and generate hydroelectric energy? What about all the solar energy which falls all over the earth? Are we negligent in not harvesting it? For that matter, we can even ask about all the solar energy which misses the earth in all the other directions. Is it going to "waste"?
My answer to this question is that it must not be the nature of the event itself which characterizes it as wasteful, but its impact on what are considered limited resources. Since Nature has plenty of solar energy available, using it inefficiently to keep the water cycle going is not wasteful. Since we have limited energy available, using it to no net effect is wasteful. This leads to the conclusion that if we figured out how to harness copious energy, and weren't short of the materials to do so, and figured out how to use it without side effects like CO2 or excess heat, that then there would be nothing inherently bad about using as much as we wanted.
An interesting and relevant corollary of this is that you can't place blame on previous generations for waste of resources they didn't yet know were limited. The fact is, almost everything we do is wasteful, but just like the cycles in nature, we find them necessary to life. Every time I go hiking or cycling and return to the starting point, I've wasted energy which must be replenished with food, which has an impact on resources to grow and ship. Any trip taken just for entertainment is a complete waste outside of our own mental health. And yet, we find all these things necessary to make life worth living - just as Nature must use Her resources to support life in general.
So, my conclusion? Do try to be smart in your use of resources, so we don't run out. But don't feel guilty about using a reasonable amount to make your life worth living. After all, if there is any point to our existence at all, it is to enjoy the world around us.