I've been challenging woo-woos for years when they start up their crap about "we can't be sure of reality."
I ask them to perform a simple experiment. They should load a pistol, put it to their heads, and pull the trigger.
If their theories of Quantum Reality are correct, then their awesome super-speedy Quantum Brain Waves should simply alter the course of the bullet...which is governed by boring, tired old non-quantum physics. Obviously no match for Quantum Reality!
When I'm feeling more liberal, I suggest they jump from a high building and Quantumly alter the nature of their impact on the way down. That should be pretty simple.
More seriously... NO!...the latest issue of SKEPTIC magazine has a good article on the Great Philosopher responsible for a lot of this extreme po-mo silliness: Jacques Diarrhea...er, Derrida.
I had the great pleasure of hearing a lecture by the guys who hoaxed the entire extreme po-mo community. They got an article published in one of its leading journals, attacking the idea of "objective mathematics."

You can find the resulting huffing-and-puffing by the po-mo community all over the web. All sorts of excuses for why an article that the real experts spotted as a hoax immediately, sailed right over the heads of the pompous po-mo asses. "Yes, we knew it was a hoax and went along with the joke..." BWA!
The SKEPTIC article mentions this embarassing moment for the Subjective Reality folks.