What makes Forth really distinctive is LIFO, not merely being postfix. You can have stack-based LIFO human languages, too, but it's very hard for humans to parse things that correspond to non-trivial nested constructs in them because of the need to maintain said mental stack. Fith is/was a conlang built on that idea:
Nice find! It may be interesting to compare Shallow Fith to Japanese grammar -- I don't know Japanese, but I have played with variations on Forth to try for better readability.
While Forth has little point nowadays, RPN still is worth keeping in mind for combining direct manipulation with programmability in UIs.
http://web.archive.org/web/20110610231636/http://www.langmak...