I’m going to argue for the existence of God from the premise that moral good and evil really exist. There are not simply a matter of personal taste not merely a substitute for I like and I don’t like.
Before I begin let’s get one misunderstanding out-of-the-way. My argument does not mean that atheists can’t be moral; of course atheist can behave morally just as a theist can behave in immorally.
Let’s start then with a question about good and evil where atheists typically propose a few possibilities among these are:
(4) Human nature and
I will show you that none of these can be the ultimate source of morality.
Why not for evolution? Because any supposed morality can change; if it can change for the good or the bad, there must be a standard above these changes to judge them as good or bad. For most of human history more powerful societies enslaved weaker societies and prosper just the way it was and no one question it; now we condemn slavery, but based on a merely evolutionary model that is an ever-changing morality, who’s to say it will not be acceptable again one day? Slavery was once accepted but it was not therefore acceptable. If you can’t make that distinction between accepted and acceptable you can’t criticize slavery and if you can make that distinction you are admitting to objective morality
What about reasoning? While reasoning is a powerful tool to help us discover and understand morality, it cannot be the source of morality. For example, criminals use reasoning to plan a murder without the reason telling them that is a wrong thing and was it reasoning or something higher than reasoning, that led those Gentiles who risk their lives to save Jews during the Holocaust? The answer is obvious it was something higher than reasoning, because risking ones life to save a stranger was a very unreasonable thing to do.Nor can conscience alone can be the source of morality. Every person has his own conscience and some people apparently have none. Himmler, chief of the brutal Nazi SS, successfully appealed to his henchmen’s consciences to help them do the right thing and murdering and torturing millions of Jews and others. How can you say your conscience is right and Himmler’s is wrong if conscience alone is the source of morality? The answer is you can’t.
Some people say human nature is the ultimate source of morality but human nature can lead us to do all sorts of reprehensible things. In fact human nature is the reason why we need morality; our human nature leads some of us to do real evil and leads all of to be selfish unkind and egocentric. I doubt you would want to live in a world of human nature was given free reign.
Utilitarianism is the claim that what is morally right is determine by whatever creates the greatest happiness for the greatest number. But to return to our slavery example if 90% of the people would get great benefit from enslaving the other 10% would that make slavery right? According to utilitarianism it would.
We’ve seen where morality can’t come from; now let’s see where it does come from.
What are moral laws? Unlike the laws of physics or the laws of mathematics which tell us what is; the laws of morality tell us what ought to be. But like physical laws, they direct and order something and that something is right human behavior, but since morality doesn’t exist physically (there are no moral or immoral atoms or cells or genes) it’s cause has to be something that exists apart from the physical world. That thing must therefore be above nature or supernatural.
The very existence of morality proves the existence of something beyond nature and beyond man. Just as a design suggests a designer, moral commands suggest a moral commander. Moral laws must come from a moral lawgiver, well, that sounds pretty much like what we know as God.
So the consequence of this argument is that whenever you appealed to morality you are appealing to God, whether your know it or not you’re talking about something religious, even if you think you are an atheist
Source: Peter Kreeft professor of philosophy at Boston College (Prager University)