"money is worth less in the future" is not a general rule but a function of inflation
That is only partially true. The time value of money is a function not only of inflation, but of other things as well, notably the value of time (e.g. human lives are finite) and opportunity costs.
In fact, one of the approaches to figuring out the proper discounting rate for future cash flows is to estimate your opportunity costs and use that.
r/Fitness does a weekly "Moronic Monday", a judgment-free thread where people can ask questions that they would ordinarily feel embarrassed for not knowing the answer to. I thought this seemed like a useful thing to have here - after all, the concepts discussed on LessWrong are probably at least a little harder to grasp than those of weightlifting. Plus, I have a few stupid questions of my own, so it doesn't seem unreasonable that other people might as well.