Here follows is my take on the discussion and lack of resolution.

I believe his/her face is the front and her/his back is well, his/her back, not commenting on other terms for certain parts back there. But that doesn't translate well.
Philatelist's argument:
In the USPOD mail was faced by hand before hand cancelling or running the stack through an automated cancelling machine. The USPS in the early 1990's brought on line an Advanced Facer Canceller System to sort mail for proper cancellation of the stamps. Thus by postal nomenclature, the address and normal stamp side is the "face" making the other side the back thus front and back, address side (front) and picture side (back).
Now the best explanation I have read on the subject is this comment, "
This thread is the reason I decided never to collect Postcards. I could never work out which side to hinge." Spoken like a true philatelist. I found that in this polling thread on the same subject from 2011 here:
https://www.stampboards.com/viewtopic.php?t=33151From a deltiologist's point of view:
Now if Google is the new "brain" for most folks here is the answer of the masses:
https://www.google.com/search?q=bac...1280&bih=550Now from a postcard collector's point of view there is the "undivided back" and "divided back" post cards of the 1900-1915 period with the divided or undivided back referring to the address side of the card.
Alas, philatelist recognize divided and undivided postal cards but, but, but....
For a quick read from another point of view,
https://www.mccarthyandking.com/dir...tcard-design , the point of view of those who use and design postcards for messaging purposes. It is a resounding, well it depends.
