[Lurker]

“However, what’s to keep states from accepting chickens, if they want, for payment of taxes, etc...”

Um, the Constitution. Once again, it’s right there in black and white. Go see if you can find it.

L

[amorphous]

I found it: make any Thing but gold and silver Coin a Tender in Payment of Debts

It plainly says, "make", NOT ANYTHING about "accepting". I see nothing which prevents states from accepting chickens for payment of taxes, if they so desired.

See what Webster says about the definition of each...