But the point is that for humans reading cards, these two things mean the same:
"if it costs from $3 to $6, trash it; otherwise gain a Curse"
"if it doesn't cost from $3 to $6, gain a Curse; otherwise trash it"
My thought process when dealing with the first instance in the absence of a card is something like "There wasn't a card, so it isn't true that it costs from $3 to $6, so a Curse has to be gained."
My thought process when dealing with the second instance in the absence of a card is something like "There wasn't a card so it didn't cost from $3 to $6, so a Curse has to be gained."
For both phrasings my thought process in the absence of a card results in a Curse being gained. Isn't your argument based on the premise that they should give different results?
I'm saying that they should give the same result; but based on the argument that the others were making in this thread - that "it costs from $3 to $6" and "it doesn't cost from $3 to $6" are both false - they give different results, because in both cases the "otherwise" clause would be the result.
OK, so you and I seem to agree that the natural interpretation of Giant is to curse when there is no card. That's good, given that it coincides with Donald X's intepretation. The same is true for Barbarian. That leaves Bounty Hunter, Sorcerer and Sorceress.
Going from the wiki texts. Telling you my rulings for today, rather than e.g. what some particular software does or what my rulings would be with hypothetical wordings. And I haven't checked where this conflicts with the wiki or other posts.
If there's no card to do the thing with:
* Bounty Hunter: +1 Action. Exile a card from your hand. If you didn't have a copy of it in Exile, +$3.
You don't get the +$3.
Here my thought process seems to give the wrong answer, which is not to say that I think it should be giving +$3, merely that my thought process ("There wasn't a card so there couldn't have been a copy of in Exile, so +$3.") doesn't give the intended result. Perhaps it's a pity that it's not phrased "+1 Action. Exile a card from your hand. If it is the first instance of it in Exile, +$3."
* Sorcerer: +1 Card. +1 Action. Each other player names a card, then reveals the top card of their deck. If wrong, they gain a Curse.
No Curse. With a more written-out-for-clarity "if wrong" it would just match Bounty Hunter.
Which suggests that my thought process would go astray here too.
* Sorceress: +1 Action. Name a card. Reveal the top card of your deck and put it into your hand. If it's the named card, each other player gains a Curse.
No Curse.
But as far as I can see this works just like Giant and Barbarian: there isn't a revealed card, so it can't be the named, so the unwritten otherwise, i.e. nothing, occurs.