@FC-in-the-UK said in #28:
> Sometimes the most obvious-looking notions are the most tricky ones. There is actually NO WAY TO DEFINE TRUTH. The proof is very simple and very ancient: if you could define truth, you could express "this sentence is not true". The self-reference is NOT an issue (this is known since the work of Gödel).
> @Akbar2thegreat @StevenEmily @Hedgehog1963 in this thought experiment you aren't an actual deity. You only are God-like in the sense that you have the power to remove Mr X's ability to feel happiness with a click of your fingers, and nothing more, nothing less.
> @kyanite111 what about sadists? What about people who enjoy exerting powers on others? What about people like Alexander the Great, Attila, Genghis Khan, Napoléon, Hitler, Putin?
>
> It is blatantly obvious that any measurement of a life lived is meaningless.
You can define "this sentence is not true" by just doing ( ph <-> ph is not true ), where "ph" is a variable and "<->" is the biconditional operator, used here to "define" ph to be the sentence "ph is not true" in the same way that the "and" operator is defined here: http://us.metamath.org/mpeuni/df-an.html
And you can "define true" as well: http://us.metamath.org/mpeuni/df-tru.html
(I could guess at what you're actually saying about Godel's incompleteness theorem and definition but I'll let you expand)
Edit: (Didn't read)
> Sometimes the most obvious-looking notions are the most tricky ones. There is actually NO WAY TO DEFINE TRUTH. The proof is very simple and very ancient: if you could define truth, you could express "this sentence is not true". The self-reference is NOT an issue (this is known since the work of Gödel).
> @Akbar2thegreat @StevenEmily @Hedgehog1963 in this thought experiment you aren't an actual deity. You only are God-like in the sense that you have the power to remove Mr X's ability to feel happiness with a click of your fingers, and nothing more, nothing less.
> @kyanite111 what about sadists? What about people who enjoy exerting powers on others? What about people like Alexander the Great, Attila, Genghis Khan, Napoléon, Hitler, Putin?
>
> It is blatantly obvious that any measurement of a life lived is meaningless.
You can define "this sentence is not true" by just doing ( ph <-> ph is not true ), where "ph" is a variable and "<->" is the biconditional operator, used here to "define" ph to be the sentence "ph is not true" in the same way that the "and" operator is defined here: http://us.metamath.org/mpeuni/df-an.html
And you can "define true" as well: http://us.metamath.org/mpeuni/df-tru.html
(I could guess at what you're actually saying about Godel's incompleteness theorem and definition but I'll let you expand)
Edit: (Didn't read)