If you knew two and two were four, would you still ask me to demonstrate it to you?
And atheists wonder why they have certain stigmas attached to them.....
Mathematics and morality are different things. I hope you agree with that.
Mathematics does indeed contain objective truths.
And - this is the important part now - you can indeed demonstrate them, if you are so asked!
Reverting to "do you really need me to?" or "what kind of person are you not to accept that!" or "No wonder your kind has certain stigmas attached to them!" is only evading this.
Basically, what you are doing here is claiming: "2+2=4, this is a demonstrable fact. I don't need to demonstrate it... but it is completely equal to the demonstrable fact that chocolade tastes good and Stockhausen's music is awful. I don't need to demonstrate that either! Everyone knows that 2+2=4!"
But mathematics is not equal to taste. And mathematics is not equal to morals. And, oh wonder!, morals are not equal to tastes.
The best comparison for morals that we could make is laws. Even Christians and other moral objectivists make this comparison - talking about the "law giver" and "moral laws" and "obligations".
Laws exist... almost everyone has experienced that. Laws are made by humans... that also we know from experience.
Laws are not "objectively right or wrong"... they are made with specific intentions and they can be subject to conditions. Again something we know from experience.
On top of that, everything that I wrote in the last paragraph is
demonstrable.
I can show it to you, if asked. I don't have to make veiled attacks on your character.
(Oh, and just for the lols... 2+2=4 is not a demonstrable fact

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