Someone who is teaching a college philosophy class writes:
We discussed Descartes’ Meditations on First Philosophy last week — specifically, concerning the existence of God — and I had students write down their best proof for God’s existence in one minute, independent of their beliefs. Attached is a particularly funny response:
Another good one was the blank sheet of paper that a student handed in…
Good attempt! The ol’ supersensible as incomprehensible fallacy has tripped so many.
There is a Real Possibility that a sharp dose of early Wittgenstein will find fertile ground here.
Your response is so sensible I cannot begin to understand it.
Here’s CS Peirce’s attempt.
https://en.wikisource.org/wiki/A_Neglected_Argument_for_the_Reality_of_God
(Actually a very good discussion of the logic of science as a prelude.)
1… 2… 3… can count on you to refer to Peirce :)
Ah, but he is such a wonderful author, he can be referenced for so many things (with apologies to Laplace https://en.wikiquote.org/wiki/Pierre-Simon_Laplace)
But with some seriousness, the _wrong headed notion_ of Descarte’s of trying to doubt everything (when you can’t really doubt what you don’t doubt) might have been behind Laplace’s priors that tried to represent no experience at all.
Peirce argued you cannot start inquiry from anywhere other than where you find yourself (bound up the prior experience and expectations) and you have to accept responsibility for those and cannot escape from trying to get them less wrong.
Also see Andrew’s serious comment below
I doubt your doubt of doubt, and raise you a doubt.
I think both are exceptionally clever answers :-)
You said, dear Descartes, that “je pense, donc je suis,”
Deriving existence from uncertainty.
Now, you are gone, and we say, “au revoir,”
Doubtless we think, René, therefore we R.
From Chapter 3, about the programming language R, of DBDA2E.
Great ones. Except we cannot even prove the existence of thought…
“Except we cannot even prove the existence of thought…”
Still, we may have a subjective prior on the existence of thought, so possibly we can do a Bayesian analysis …
Martha:
Data-based prior, please! Or, if you must refer to “subjective prior,” please also talk about “subjective likelihood function,” “subjective logistic regression,” “subjective additive linear model,” etc.
Andrew,
I can’t tell: Is your response here an objection to the use of personal probability for this problem, or just with the terminology “subjective”?
JD
JD:
I have two objections. First, I think our models should be data-based as much as possible so I don’t like the attitude that the prior is something that people just pull out of their heads. Second, to the extent that specifying a Bayesian prior distribution is subjective, so are the other choices in a model: the subjective logistic regression, subjective additive model, etc.
To say it again: From a normative perspective, I want Bayesian priors to be data-based, and I worry that the “subjectivist” terminology is used by people to get themselves off the hook and think that any prior they choose is ok. From a descriptive perspective, I think it’s inaccurate and misleading to single out the prior distribution as having some subjective status that is not present in other aspects of a statistical model or statistical procedure.
Hey, it was intended as humorous. Maybe I shoulda added a smiley face?
It is difficult to convey intonation in typed speech.
As a believer I agree with what the student wrote. Proving the existence of God is a non-empirical, personal matter involving faith. I believe in God because of experiential events involving the Spirit. My faith is not based on external events.
Or as Tertullian memorably said in the 3rd century: Credo quia absurdum. https://en.wikipedia.org/wiki/Credo_quia_absurdum
Nothing absurd about spiritual evidence mon ami, unless you have never had a spiritual experience, I suppose.
Nothing could be more absurd, if it tried a little harder.
Agreed, with a little effort nothing could finally amount to something.
That’s the Spirit! If we all Chip in and Do our Part, we’ll get the job done!!
No! No, you didn’t! You published a page from David Brooks’ secret diary! He’s gonna be really angry.
…yeah, straying into philosophy/metaphysics is risky for statisticians because objective probability is impossible to prove. Philosophic issues mesh poorly with worldly science practitioners.
Quantifying limited subjective “data” does not make it objective.
That Quantum Bayesianism/QBism stuff really muddies the waters pretty well.
The kid’s assertion in the Philosophy class has a lot of formal philosophical support — one’s perceived existence confirms only that the subjective probability of such a perception is non-zero.
All else is non-verifiable, objectively. Bummer
(“Reality is an illusion” — Albert Einstein)
I am glad my professors never asked me to write my best one minute proof of the Fermat theorem. If I think about it, not even the most trivial theorem. Why is holding the concept of god in such low regard?