Sam Harris' B.A. in philosophy doesn't appear to be sufficient for making him a competent philosopher. The question of whether morality can and does exist objectively without God is entirely a metaphysical question - making his background in neuroscience entirely irrelevant. His arguments, as do all atheists' arguments, depend on fundamental tenets like materialism, naturalism, empiricism, etc. - none of which are coherent. Empiricism is self-refuting; it holds that empirical observation is the only way to know truth, but it can't show that statement to be true. Belief that science is the only way to know truth, is also self-refuting, as there's no way to conduct an experiment to test if that's true. It's also false simply because truth can be obtained via methods like logical deduction, completely independent of science. Naturalism is self-refuting; if our ability to conceive of truth exists only because it has naturally evolved to be as it is, and nature selects only for traits that help us survive, and knowledge of truth isn't necessary for our survival, then there's no reason any of our conceptions of truth would be correct and Sam Harris shouldn't believe anything he says.
Sam Harris is a dumbass
Materialism is false; in order for it possibly to be true, one would have to believe ideas and concepts exist physically and objectively. Matter can only produce emergent properties. Emergent properties don't exist; that is, they only exist as ideas. There is no such thing as mind-independent, objective emergent properties, in the same way there is no such thing as mind-independent, objective information. Only the mind gives these things meaning. The mind objectively exists. Thus the mind isn't an emergent property. Thus the mind can't be produced by matter. Thus the mind is immaterial. Thus materialism is false. As you should infer, when science is conducted by someone who isn't a logician, it allows for logical incoherencies to be overlooked or ignored, and makes evidence susceptible to being interpreted in accordance with bias.
In order for objective morality to exist in a materialistic world, as Sam Harris believes, it would need to be an abstract object or exist in physical objects. I don't know if he dismisses this necessity all together, but at the very least, he presupposes at least one of these to be true. This is because he presupposes God doesn't exist, demonstrably from a number of these logical fallacies: straw man ('God is a magical sky wizard'), appeal to ridicule ('lol they actually believe this'), begging the question (assuming his conclusion, like that morality objectively exists in a materialistic world, and -then- trying to explain how it works), red herring (anything irrelevant like 'What matters is that we have morality'), appeal to need ('We don't need God'), appeal to emotion ('God was bad and atheism is the only true enlightenment'), appeal to what should be ('It would be bad for God to exist'), genetic fallacy ('All religions correlate with certain cultures, therefore they are all false'), argument from ignorance ('I don't recognize evidence for God, therefore He's unlikely to exist'), or - and this is the most popular one, responsible for most atheist's delusions about atheism being synonymous with "reason" - appeal to the stone (dismissing something as obviously ridiculous without giving proof).
Consequently, Sam assumes morality is material and works his way from there. He certainly didn't arrive at that conclusion logically. He explains how our sense of morality has evolved to be as it is for our survival, but this doesn't imply morality objectively exists, only that subjective morality exists. In Sam's world view, unless he's cognitively dissonant or profoundly logically inconsistent, morality is objectively meaningless - nihilism is an inescapable consequence of atheism. He tries to confuse and conflate subjective meaningfulness with objective meaningfulness, but that's just an appeal to emotion. They simply aren't the same thing - nothing objective is contingent on our thoughts. Explaining how something would be plausible does not imply the probability of that thing being true. Sam Harris does nothing to show the existence of God is unlikely or ridiculous.
People who think of the existence of God as a ridiculous notion, presumably by choice, imagine Him as some limited being who's unlikely to exist by definition. God is generally defined as being omnipotent, omniscient, omnibenevolent, transcendent, and ultimately incomprehensible. Imposing purposely silly definitions on Him (or any definition), aside from being an appeal to ridicule, does not function as a valid reduction to absurdity because any and all imposed definitions conflict with His actual definition. For example, a "flying spaghetti monster" is either not omnipotent by definition, or its form isn't necessary and therefore arbitrary and non-definitive. If or when the intention is merely to show God is "as ridiculous" as any fantastical thing using false analogies, it is only a redundantly-fallacious appeal to the stone. It's also akin to saying "Look, I can make things up. Therefore your God is made up," and yet these are the kind of unsophisticated arguments atheists use, presumably all because they refuse to conceive of possibility outside our comprehension, lest they have to admit we may be held accountable to something outside ourselves.
The existence of God isn't ridiculous, anymore than the existence of minds, multiple dimensions, fundamental forces, ideas, concepts, thoughts, good, evil, purpose, meaning, physical constants, logical constants, existence in general, etc. are ridiculous. You might be tempted to contest something like "But we observe these things." No, you don't. You only observe their effects.
Arguments against Sam Harris' belief of the existence of objective morality in a Godless world:
Subjective relativism is self-refuting. If subjective relativism were true, the proposition "subjective relativism is false" would be paradoxical and couldn't exist. The proposition can exist, as I've demonstrated. Therefore subjective relativism is false. Therefore subjective morality isn't necessarily objectively correct.
1. There is only the conscious and the nonconscious. (p ^ p' = everything)
2. We know inductively that the inanimate (nonconscious) is not moral.
3. In some possible world, there is only the nonconscious.
4. In some possible world, there is no morality. (from 2 and 3)
5. Morality is contingent.
6. Morality is not contingent on the nonconscious. (from 2)
7. Morality is contingent on the conscious. (from 1, 5, and 6)
8. The objective is by definition independent of human or limited consciousness.
9. Morality can be objective if and only if God exists. (from 7 and 8)
10. Everything is objective or subjective.
11. If God doesn't exist, morality is only subjective. (from 9 and 10)
1. If God exists, morality exists as a Godly idea.
2. Godly ideas exist objectively.
3. If God exists, morality exists objectively.
4. If God doesn't exist, materialism is true.
5. The only thing that exists outside of minds is matter and possibly abstract objects.
6. Morality cannot be composed of matter.
7. Abstract objects are only concepts.
8. Concepts cannot exist objectively.
9. Abstract objects do not exist objectively.
10. If morality is an abstract object, it does not exist objectively.
11. Morality cannot exist outside of minds.
12. If God doesn't exist, morality only exists as a human idea. (from 6 and 10)
13. Human ideas don't exist objectively.
14. If God doesn't exist, morality doesn't exist objectively.
15. Therefore, if God doesn't exist, morality is only subjective, and it's objective only if God exists.
In conclusion, Sam Harris is demonstrably a dumbass.
Is this considered copypasta at this point? Did you write this?
It's funny, your like a turtle on his back flailing. Especially when it comes with your mission in life to denigrate Sam Harris.
we already know this
Sam Harris is a idiots idea what a smart person is like.