I am alright with accepting as an axiom that I exist. I see no reason why I should be cautious of assigning a probability of 1 to this statement. I am infinitely certain that I exist.
The search keyword for reasoning that uses “I exist” as a derivation step in arguments is “anthropic reasoning”. This is squarely in the middle of a thicket of very hard, mostly unsolved research problems, and unless you have a research-level understanding of that field, you probably shouldn’t assign ordinary confidence, let alone axiom-level confidence, in anything whatsoever about it.
I choose to accept as an axiom that I exist. For if I do not exist, everything else is meaningless. If I doubt my own existence, what then can I believe in? What belief can I have if not my own existence?
I exist.
(I’ve taken note of anthropic reasoning, and may read up on it later, but it wouldn’t change the axiom).
There are decision-theoretic contexts in which you don’t exist, but your (counterfactual) actions still matter because you’re being simulated or reasoned about. These push on corner cases of the definitions of “I” and of “exist”, and as far as I know are mostly not written up and published because they’re still poorly understood. But I’m pretty sure that, for the most obvious ways of defining “I” and “exist”, adding your own existence as an axiom will lead to incorrect results.
I’m tempted to agree with DragonGod on a weaker form (or phrasing) of the “I exist” proposition:
I would defend the proposition that my feeling of subjective experience (independent of whether or not I am mistaken about literally everything I think and believe) really does exist with a probability of 1. And even if my entire experience was just a dream or simulated on some computer inside a universe where 2+2=3 actually holds true, the existence of my subjective experience (as opposed to whatever “I” might mean) seems beyond any possible doubt.
Even if every single one of my senses and my entire map of reality (even including the concept of reality itself) was entirely mistaken in every possible aspect, there would still be such a thing as having/being my subjective experience. It’s the one and only true axiom in this world that I think we can assign P=1 to.
Especially if you don’t conceive of the word “exist” as meaning “is a thing within the base level of reality as opposed to a simulation.”
The search keyword for reasoning that uses “I exist” as a derivation step in arguments is “anthropic reasoning”. This is squarely in the middle of a thicket of very hard, mostly unsolved research problems, and unless you have a research-level understanding of that field, you probably shouldn’t assign ordinary confidence, let alone axiom-level confidence, in anything whatsoever about it.
I choose to accept as an axiom that I exist. For if I do not exist, everything else is meaningless. If I doubt my own existence, what then can I believe in? What belief can I have if not my own existence?
I exist.
(I’ve taken note of anthropic reasoning, and may read up on it later, but it wouldn’t change the axiom).
There are decision-theoretic contexts in which you don’t exist, but your (counterfactual) actions still matter because you’re being simulated or reasoned about. These push on corner cases of the definitions of “I” and of “exist”, and as far as I know are mostly not written up and published because they’re still poorly understood. But I’m pretty sure that, for the most obvious ways of defining “I” and “exist”, adding your own existence as an axiom will lead to incorrect results.
I’m tempted to agree with DragonGod on a weaker form (or phrasing) of the “I exist” proposition:
I would defend the proposition that my feeling of subjective experience (independent of whether or not I am mistaken about literally everything I think and believe) really does exist with a probability of 1. And even if my entire experience was just a dream or simulated on some computer inside a universe where 2+2=3 actually holds true, the existence of my subjective experience (as opposed to whatever “I” might mean) seems beyond any possible doubt.
Even if every single one of my senses and my entire map of reality (even including the concept of reality itself) was entirely mistaken in every possible aspect, there would still be such a thing as having/being my subjective experience. It’s the one and only true axiom in this world that I think we can assign P=1 to.
Especially if you don’t conceive of the word “exist” as meaning “is a thing within the base level of reality as opposed to a simulation.”
A simulation exists. A simulation of me is me.
I am my information, and a simulation of me is still me.