P1: If objective moral values exist, then God exists.
P2: Objective moral values exist.
C: Therefore God exists.
It's a nice straight forward one. It's easy to see that P1+P2=C if they're both true.
So the question is, are P1 and P2 true?
The short answer is yes. But let's look closer anyway.
P1 is the one most people seem to get stuck on. It's possible that many people forget that each premise (P) comes with lots of backing support. They see the sentence alone and wonder why they should believe it. Well, let's find out.
The question is about objective moral values. If they moral values are objective, then they are true no matter what anyone thinks about them. Opinions don't matter. So how can morals (which seem to be very much based on opinions) be objective?
For that to be the case, moral values have to be compared to some kind of objective standard. There has to be something that you can point at and say "That is what good looks like" and see if the specific moral value measures up.
Different people have explained this in different ways. C.S. Lewis has possibly the most famous example.
He asks you to think of a crooked line. How do you know it's crooked? Because you know what a straight line looks like. If the line you're imagining is not a straight line, then it's crooked.
So in the same way, to know something is bad, you have to know what 'good' looks like. There has to be a standard for goodness.
So what could be that standard? It would have to be something that is absolutely 100% good. It can't be 99% good. You can't say, that's almost what good looks like, but real good is a bit better. You have to know what the 100% looks like, because without it, you wouldn't ever be able to figure out what 99% looked like.
If we look to nature, there isn't anything that we can call 100% good on it's own merit. You might say something like "dolphins are good, let's call dolphins the standard", but that wouldn't work because there's no reason apart from your own opinion to say that dolphins are good.
Some people might say that 'good' is an abstract concept that doesn't need to be grounded in an object. But then how can you know what 'good' is? If it's just a concept, then you're just defining what it is. That makes it subjective. Someone else could define it differently.
Some might go a step further and say that 'good' is a kind of abstract object. It just exists as a kind of immaterial entity. (This is called Platonism.) If this is true, then 'good' itself could be an objective standard for morality. This type of existence is a problem for naturalists and materialists who don't have room in their world-view for immaterial entities, so it's strange that they might suggest that 'good' just exists, but are adamant that God doesn't. Once they open the door to necessary, immaterial entities, they've left it wide open for God. Platonism also raises a whole bunch of other problems. The concept of 'good' as an actual object is based on our knowing what 'good' is, and having an ideal version of it in mind. Look at your bookshelf. Pick out a book. Let's say 'The Arabian Nights'. If that book was burned, would 'The Arabian Nights' no longer exist? No, just that book. If all the copies in the world were burned, would it no longer exist? No, just the physical copies. Even if the original was burned, it still probably wouldn't be fair to say that 'The Arabian Nights' doesn't exist. It still lives on as an idea, or a memory, or a concept. But those things don't equal real, or have any way of impacting the world. So to say anything exists in a platonic way, would mean that anything we can dream up exists in a platonic way. If you commit yourself to thinking 'good' is a platonic reality, you also have to commit to thinking unicorns are at least platonically real too. If it's all based on ideas and human created concepts, it's not necessarily connected to reality, and is clearly subjective.
The only way you can have an objective standard is if it's something that defines 'good' in a way that no one can disagree on, no matter how hard they try. This doesn't mean that people won't disagree, but it does mean that those that do are actually truly wrong. Christianity (among other faiths) teaches that God is perfectly good. Or if you like, he's the embodiment and personification of 'goodness'. That is a suitable objective standard.
So for objective moral values to exist, they need an objective grounding, and it seems that the only potential grounding is in a 100% perfectly good entity (which describes God).
Some people get this stuff confused with some kind of 'divine command theory', but the fact is that the MA has no connection to anything of that type. It just says that God is perfectly good, not that he forces his goodness onto anyone.
A lot of atheists like to say that 'human well-being and flourishing' is a suitable alternative objective standard. What they seem to be missing is that they're assuming that human well-being is an objective purpose, but they have no reason to. If atheism is true, there's no reason to think that humans have any moral worth, and so no reason to think their well-being or flourishing is good.
In fact, we have reason to believe the opposite. We know that all humans die, and that the human race will go extinct, and that the planet will burn up when the Sun explodes, and that the universe will eventually die in heat death. Ultimately, no matter how well or badly humans flourish, they'll all end up the same. So why bother? Yes, individuals will feel happier for a short time, but it's all insignificant.
Once you bring an immortal soul into the picture, human actions, well-being, and perhaps even flourishing become things that do have worth. The things people do will hold weight for eternity.
So it's clear that although without God, everything is meaningless, that doesn't mean people can't take care of each other while it lasts.
So this can be summed up like this:
P1. Objective moral values require an objective moral standard.
P2. The only potential objective moral standard would be an entity that represents 100% goodness.
P3. The only potential entity that represents 100% goodness is God (the greatest conceivable being).
C: Objective moral values require God.
So all that rolled up together makes P1 of the Moral Argument. Clearly P1 on it's own doesn't mean that God exists and makes no assumption that he does. It just makes it clear that the only way objective moral values could exist is if they are grounded in God's nature.
So onto P2: Objective moral values exist.
Now it might surprise you that I'll admit that P2 is a premise I haven't really got any evidential support for.
However, I will say that nobody lives as though P2 is false. Everyone acts as though moral values are objective.
We have laws, law enforcers, courts, judges and juries that are all based on us behaving according to a specific set of moral values. If moral values are subjective then that means our laws are forced on us by people in a position to pretend their own opinions matter. But if moral values are objective, then hopefully our laws reflect the things that are truly right and truly wrong.
Part of our law is that murder is wrong. Under no circumstance is murder allowed. Most of us would say that it is a fact that murder is wrong. If we say that it isn't a fact, but just an opinion, then we haven't really got a right to put someone in prison if they commit murder. They're just being unfashionable. They haven't really done something wrong.
If laws are subjective then they're just based on majority opinions, but majority opinions don't equal truth. It's possible for everyone in the world to have the same opinion about something, and that thing turn out to be untrue.
But if moral values are objective, then that means murder really is factually wrong. Which would then mean we are justified to imprison murderers to keep society safer.
This is kind of a black and white explanation. I'm saying with God, there is always a correct answer to the question "Is what I'm doing right or wrong?", while without God the answer is always "there is no such thing as right or wrong." It's essentially a choice between theism or nihilism (everything is meaningless).
But that doesn't go to say that we can't pretend that some things are important. We all might individually care about our families, and so will do what we can to look after them. So we might make laws to reflect that. So if God doesn't exist, and everything is meaningless, people can still come up with a system that makes life comfortable. There's no need to start murdering and stealing just because you don't believe in God. The only proviso is that you have to admit that ultimately, it is all meaningless and you're just trying to get on as best you can. So having a moral system based on something subjective like 'human well-being' is basically nihilism coupled with a comforting lie.
You're free to pretend things have meaning, but that doesn't mean that they do. But the moment you say something like 'murder is actually wrong', then you're saying 'the line is crooked'. It requires an actual 'good' and an actual 'straight line'. Without that objectivity, then murder carries the same moral value as tying your shoelaces.
Which is what P2 of the MA (Moral Argument) boils down to. You can accept that objective moral values exist, and so accept the conclusion that God exists, or you can deny objective moral values and accept that ultimately every moral decision anyone makes is meaningless.
