I am really not well-informed on the role of energy in the technological advancement, because I have not given it much thought, but lets take a few examples: Internet is one of the most powerful group of technologies working together: Computers, Networking, Writing, Multimedia etc. You might say that it's working only because you're burning a lot of coal to keep servers up and running, therefore you need a lot of energy to support such a powerful technology. But just think about it: Is it possible to enjoy this conversation without these technologies, even if you have at your disposal, say, a lot of coal to burn? What I am trying to say is: It's a combination of technology and energy which makes life easier for mankind. But yes, as I am writing this I am realizing that we might question the importance of one over the other. it's energy which made implementation of great ideas possible. I think I have to agree upon it.
Lets take example of E = mc^2. Einstein's ideas which built on other thinkers of past made it possible for us to untap most powerful resources for energy. Forget about the misuse it was put to as it's not in the scope of present discussion, but had it not been for Science and technology, this energy which was always present before us would not have been uncovered and made obvious for use.
Energy has always been there in untapped form. you might say that untapping of energy made it possible for us to get such a rapid advancement in technology, but I think it's only one side of the picture. I think that there is a feedback loop: Technology and Science work together to get more energy and this energy in turn makes further research and innovation possible and this is a loop in which both Technology and Energy improve with mutual cooperation.
Take another example: Lets take evolution also into the account. As I have come to know, by reading and watching TV and movies; our ancestors were most benefitted by 1. Weapons to get food. 2. Fire to make it tastier and digestible. 3. Wheel. 4. Farming and organized living.
Now, what might good food have done for them? It might have given our ancestors more energy to get more food and hence might have helped in getting adapted for their survival against forces of nature. Weapons, Fire, Wheel were all technology and Science and so were farming and organized living. They all were needed in the first place to get more energy. But wait, I think that at any given point of time in history you cannot pin-point if it was only Technology or Energy which contributed into the advancement of humanity.
In any case, the moot point seems to be 20th century scene. But can we really isolate 20th century from all past centuries, as my friend has suggested? I think no. Even if it was unique in a way because we came to know about some huge powerful resources for energy, I think technology played a great part and there will be many such discoveries. But wait: I am sure about fossil fuel resources: You say that it was basically oil which made this great advancement(compared to previous centuries) possible. Has any fuel, more powerful than this been discovered in last two hundred years? Yes, nuclear energy, fission and fusion is the answer. But has it been put to as much of use as fossil fuels? No. What are the reasons? Perhaps technology is yet not robust enough. Why? I don't know. May be technology is already in place but its implementation requires vast amounts of energy which we cannot afford as energy deficiency is already threatening. Which means that we need energy to get more energy! Or are we missing something? Is it that we just need more innovation and there would be easier ways of untapping and implementing nuclear resources? I am confused.
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