This invaluable piece of advice comes from one of the old Lord of the Rings text adventures, which were released on all those old 8-bit machines. I played it on a Commodore 64.
While nowadays the claim
that a simple adventure game parser could put a significant strain on a machine seems vaguely monstrous, revolting and downright crazytalk, the delightful interface to these games (I'm thinking of volume I in particular) was capable of thinking far too hard about any sentence not in the usual imperative-verb + object format. But usually, it fared well enough on simple verb + object constructions.
Well, there came a point, not too far into the first game, when you, as Frodo, found yourself standing somewhere in the Shire wondering what to do next, in the company of Samwise Gamgee and in the possession of a match and some other no doubt valuable pieces of adventure-game inventory, such as your trusty elven sword, your sack, your brass lantern and all the rest. So you did what any self-respecting adventurer would do in similar straits, and you try every combination of objects you have with everything in your environment. Even
put sam in sack
light sam with match.
The last one of these was the culprit. After entering it, the computer would freeze in thought for about five seconds and then say, with confidence:
You cannot burn
Since you hadn't been given your cursor back and there was no period at the end, you knew that there was more to come. After a little while longer of struggling with the obtuseness of light sam with match, it would add
and fret a bit more. Protracted pause. You could almost feel the poor little machine grappling with self-doubt, worrying that it was coming out with something stupid while everyone was watching it with increasing annoyance, tapping their feet and tut-tutting. Then, in a final burst of desperation it would finish with:
and hope that you didn't notice anything amiss.
What I have never understood was where the (a) eastern came from. There was nothing particularly eastern there.
I like to think sometimes, when I'm in a certain mood, that this sudden burst of real, human-level rubbish from the program, was something like the first glimmerings of an emergent intelligence, a sort of desperate, embarrassed Artificial Stupidity bursting forth from the unconscious matter.
But most likely it was just an invalid null pointer dereference.