Glass's description sounds like it could be a somewhat misremembered recollection (or a deliberate elaboration) of a very short tale presented by Derek Parfit as a thought experiment, at the beginning of Chapter 10, "What We Believe Ourselves to Be" in Parfit's 1984 philosophy book Reasons and Persons.
There is no circus or million dollar reward in Parfit's story, but the story otherwise has a lot of similarities to Glass's description. The main character in Parfit's story, after some initial trepidation, starts using a "teletransporter" to make trips to Mars. The teletransporter destroys the person atomically, transmits the data, and the person is reconstituted on Mars. Subjectively, the main character loses consciousness, and wakes up after what seems a moment. After some years of using it, however, the character one day uses it and doesn't get the usual loss of consciousness, and is still in the room on Earth. He's informed that the transporter did still work; the facility has merely upgraded to a new version that transmitted his blueprint without destroying his atoms on Earth. Unfortunately, there still are some kinks to work out. He's informed that the new teletransporter version caused him (the still-on-Earth him, that is) to have cardiac damage that will kill him in a few days. Not to worry though, because the version of him on Mars is as healthy as usual.
I wondered if versions of this thought experiment could go back further, since Parfit immediately afterward wrote the following paragraph quoting Willard Van Orman Quine regarding such thought experiments:
What can we learn from this imaginary story? Some believe that we can
learn little. This would have been Wittgenstein's view.ⁱ And Quine
writes: "The method of science fiction has its uses in philosophy,
but... I wonder whether the limits of the method are properly heeded.
To seek what is 'logically required' for sameness of person under
unprecedented circumstances is to suggest that words have some logical
force beyond what our past needs have invested them with."²
The full paragraph from the W.V.O. Quine review (Quine, W. V. O. 1972. "Book Review: Identity and Individuation, Milton K. Munitz, editor". Journal of Philosophy 69 (no. 16): 488-497) is:
Shoemaker's "Wiggins on Identity" begins with a lively examination
of Wiggins' doctrine that "every identity statement stands in radical
need of the answer to the question same what?" Shoemaker cites
passages to show that Wiggins does not really hold the doctrine, once
propounded by Geach, which these words suggest, but rather the
reasonable doctrine that you cannot evaluate most identity statements
without getting clear on what things are being identified. Later he
examines Wiggins on personal identity, where the reasoning veers off
in familiar fashion into speculations on what we might say in absurd
situations of cloning and transplanting. The method of science
fiction has its uses in philosophy, but at points in the
Shoemaker-Wiggins exchange and elsewhere I wonder whether the limits
of the method are properly heeded. To seek what is "logically
required" for sameness of person under unprecedented circumstances is
to suggest that words have some logical force beyond what our past
needs have invested them with.
"Wiggins on Identity" was being reviewed as part of Quine's book review of the collection Identity and Individuation (Milton K. Munitz, editor. New York: NYU Press, 1971), but if it's the same paper (not just the same title), it appears to have been previously published in Philosophical Review Vol. 79, (OCT 1970): 529-544. That paper has some brain-pattern copying scenarios, but not a Mars story.
So that was a dead end; as far as I can tell, the Mars teleportation story originated with Parfit. If Glass did read some version involving a circus and a million dollars, I suspect it was someone else expanding on Parfit's idea.
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