If you're wondering why you seem to be getting more forgetful, you may find an answer in this very interesting podcast
from The Sunday Edition, hosted by Michael Enright who is probably Canada's best radio journalist.
I found it extremely enlightening and...um, er, wait, it'll come to me.....
iMac (Retina 5K, 27", 2017), 3.4 GHz Intel Core i5, 8GB RAM, 2400 MHz DDR4
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Canon MX710 Printer
Epson Perfection V500 Photo Scanner
Time Machine on 320GB OWC Mercury OTG Pro
Super Duper on 500GB OWC Mercury OTG Pro