Calculus Interruptus

Yes, I'm still working on the doors for my workshop, but I'm also trying to organize all the things I've accumulated for far too long.

Do you ever feel like you've lived a few lives in your lifetime?  This is from my days as a university student at McMaster University in Hamilton, ON about 30 years ago. These are just a few of a pile of study cards I had written to help me remember some of my Calculus terms and equations:

The good old days... unfortunately, in all honesty, I can't remember how to do any of it now.

Believe it or not, I miss it.  Do YOU have a previous life?