Here's something I couldn't do five years ago: field work (i.e., hiking, climbing, kneeling, getting up again). Of course I can do that now not because I'm smarter but because I got a new knee. I dunno. Define smart. Because I've continued to be active in research in my field, I know a heck of a lot more than I did five years ago, mostly because we've made some exciting discoveries in the last five years. Does that make me smarter?