Let me first define what I mean by ‘making a difference…’ because there is a lot of mischief about that in common language. Because it’s been a slogan. Because it has been a bromide for so long.
OK, explanation: if I am hired to design a system that reduces the carbon dioxide load… to turn around the Global Warming… I am asked to ‘make a difference’, i.e. to alter the future.
If I didn’t do that, but a lot of people are now arguing about it…
If I didn’t do that, but a few people in rich countries are using wind power and solar power… did I make a difference? No.