Comment by jychang | Hacker News Reader

Comment by jychang | Hacker News Reader

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Strong disagree.

Your argument basically is a professional motte and bailey fallacy.

And you cannot conclude objectivity by consensus. Physicists by consensus concluded that Newton was right, and absolute... until Einstein introduced relativity. You cannot do "proofs by feel". I argue that you DO need to answer the deep problems in mathematics to prove that 1+1=2, even if it feels objective- that's precisely why Principa Mathematica spent over 100 pages proving that.

In fact, I don't need to be a professional philosopher to counterargue a scenario where killing a baby for sport is morally good. Consider a scenario: an evil dictator, let's say Genghis Khan, captures your village and orders you to hunt and torture a baby for sport a la "The Most Dangerous Game". If you refuse, he kills your village. Is it ethical for you to hunt the baby for sport? Not so black and white now, is it? And it took me like 30 seconds to come up with that scenario, so I'm sure you can poke holes in it, but I think it clearly establishes that it's dangerous to make assumptions of black and whiteness from single conclusions.

[1] https://en.wikipedia.org/wiki/Motte-and-bailey_fallacy

> Your argument basically is a professional motte and bailey fallacy.

No it isn't. A "motte-and-bailey fallacy" is where you have two versions of your position, one which makes broad claims but which is difficult to defend, the other which makes much narrower claims but which is much easier to justify, and you equivocate between them. I'm not doing that.

A "companion-in-the-guilt" argument is different. It is taking an argument against the objectivity of ethics, and then turning it around against something else – knowledge, logic, rationality, mathematics, etc – and then arguing that if you accept it as a valid argument against the objectivity of ethics, then to be consistent and avoid special pleading you must accept as valid some parallel argument against the objectivity of that other thing too.

> And you cannot conclude objectivity by consensus.

But all knowledge is by consensus. Even scientific knowledge is by consensus. There is no way anyone can individually test the validity of every scientific theory. Consensus isn't guaranteed to be correct, but then again almost nothing is – and outside of that narrow range of issues with which we have direct personal experience, we don't have any other choice.

> I argue that you DO need to answer the deep problems in mathematics to prove that 1+1=2, even if it feels objective- that's precisely why Principa Mathematica spent over 100 pages proving that.

Principia Mathematica was (to a significant degree) a dead-end in the history of mathematics. Most practicing mathematicians have rejected PM's type theory in favour of simpler axiomatic systems such as ZF(C). Even many professional type theorists will quibble with some of the details of Whitehead and Russell's type theory, and argue there are superior alternatives. And you are effectively assuming a formalist philosophy of mathematics, which is highly controversial, many reject, and few would consider "proven".

> But Principia Mathematica was (to a significant degree) a dead-end in the history of mathematics. Most practicing mathematicians have rejected PM's type theory in favour of simpler axiomatic systems such as ZF(C). Even many professional type theorists will quibble with some of the details of Whitehead and Russell's type theory, and argue there are superior alternatives. And you are effectively assuming a formalist philosophy of mathematics, which is highly controversial, many reject, and few would consider "proven".

Yeah, exactly. I intentionally set that trap. You're actually arguing for my point. I've spent comments writing on the axioms of geometry, and you didn't think I was familiar with the axioms of ZFC? I was thinking of bringing up CH the entire time. The fact that you can have alternate axioms was my entire point all along. Most people are just way more familiar with the 5 laws of geometry than the 9 axioms of ZFC.

The fact that PM was an alternate set of axioms of mathematics, that eventually wilted when Godel and ZF came along, underscores my point that defining a set axioms is hard. And that there is no clear defined set of axioms for philosophy.

I don't have to accept your argument against objectivity in ethics, because I can still say that the system IS objective- it just depends on what axioms you pick! ZF has different proofs than ZFC. Does the existence of both ZF and ZFC make mathematics non objective? Obviously not! The same way, the existence of both deontology and consequentialism doesn't necessarily make either one less objective than the other.

Anyways, the Genghis Khan example clearly operates as a proof by counterexample of your example of objectivity, so I don't even think quibbling on mathematical formalism is necessary.

> Consider a scenario: an evil dictator, let's say Genghis Khan, captures your village and orders you to hunt and torture a baby for sport a la "The Most Dangerous Game". If you refuse, he kills your village. Is it ethical for you to hunt the baby for sport?

You aren't hunting the baby for sport. Sport is not among your reasons for hunting the baby.

Actually, I think "The Most Dangerous Game" is a good analogy here. At the end of the story, the protagonist IS hunting for sport. He started off in fear, but in the end genuinely enjoyed it. So likewise- if you start off hunting a baby in fear, and then eventually grow to enjoy it, but it also saves your village, does that make it evil? You're still saving your village, but you also just derive dopamine from killing the baby!

This actually devolves into human neuroscience, the more I think about it. "I want to throw a ball fast, because I want to win the baseball game". The predictive processing theory view on the statement says that the set point at the lower level (your arm) and the set point at the higher level (win the baseball game) are coherent, and desire at each level doesn't directly affect the other. Of course, you'd have to abandon a homunculus model of the mind and strongly reject Korsgaard, but that's on shaky ground scientifically anyways so this is a safe bet. You can just say that you are optimizing for your village as a higher level set point, but are hunting for game at a slightly lower level set point.

Note that sport is not a terminal desire, as well. Is a NBA player who plays for a trophy not playing a sport? Or a kid forced to play youth soccer? So you can't even just say "sport must be an end goal".

To clarify my principle: "It is gravely wrong to inflict significant physical pain or injury on babies, when your sole or primary reason for doing so is your own personal enjoyment/amusement/pleasure/fun"

So, in your scenario – the person's initial reason for harming babies isn't their own personal enjoyment, it is because they've been coerced into doing so by an evil dictator, because they view the harm to one baby as a lesser evil than the death of their whole village, etc. And even if the act of harming babies corrupts them to the point they start to enjoy it, that enjoyment is at best a secondary reason, not their primary reason. So what they are doing isn't contravening my principle.

Well, now that's just moving the goalposts >:( I had a whole paragraph prepared in my head about how NBA players actually optimize for a greater goal (winning a tournament) than just sport (enjoying the game) when they play a sport.

Anyways, I actually think your statement is incoherent as stated, if we presume moral naturalism. There's clearly different levels set points for "you", so "sole reason" is actually neurologically inconsistent as a statement. It's impossible for "sole reason" to exist. This radically alters your framework for self, but eh it's not impossible to modernize these structural frameworks anyways. Steelmanning your argument: if you try to argue set point hierarchy, then we're back to the NBA player playing for a championship example. He's still playing even if he's not playing for fun. Similarly, hunting a baby for pleasure can still be hunting for a village, as The Most Dangerous Game shows.

More generally (and less shitposty), the refined principle is now quite narrow and unfalsifiable in practice, as a no true scotsman. How would you ever demonstrate someone's "sole or primary" reason? It's doing a lot of work to immunize the principle from counterexamples.

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