The Plot of the Phantom, a text adventure that took 40 years to finish

Nice job. I think it might be worth adding a few more verb synonyms to make the parser a little bit less strict - what's a few more years of development. :)

Like many other devs I also dipped my feet in the world of interactive fiction. As a kid I was just learning about concepts such as inheritance / OOP / etc. so I went a bit overboard on the ontology.

I remember pretty early on making a rather large mistake in that regard when a friend who was beta-testing the game for me at the time typed in commands like "get key", "get sword", "get ye flask", and then "get Aldwin" to which the game merrily replied "OK" and promptly stuffed an entire human being into the player's inventory.

I remember writing one of these and typing "put bag in bag" and then being confused why the bag disappeared from the world.

Should have done it the other way around

Much better to have the world disappear from the bag.