“There are no objective values.” Not one to waste opening lines, that’s the startling first sentence of J L Mackie’s Ethics: Inventing Right and Wrong. (He didn’t mince words in subtitles either.) An Oxford philosopher, born in Australia 100 years ago this month, his thoughts about metaphysics, logic, and causation still get a hearing in classrooms and conference halls. But what really grabs those inside and outside the ivory tower are his arguments for atheism and scepticism about ethics. His work, worth returning to as the anniversary approaches, is filled with arguments and counter-arguments, so brace yourself for a few premises and conclusions.

In The Miracle of Theism, published posthumously in 1983, Mackie argued that “the question whether there is or is not a god can and should be discussed rationally and reasonably… it can yield definite results.” The results, for Mackie, make a case for atheism. His target was not some ill-defined New Age divinity, but the all-knowing, powerful, perfectly good, omnipresent, eternal creator at the centre of Judaism, Christianity and Islam. Despite centuries of trying, Mackie argues, philosophers and theologians haven’t managed a persuasive proof of the existence of God.

With characteristic rigour he worked through the best of the debate. He looked at David Hume’s treatment of miracles. If you think a miracle is evidence of God’s existence, bear in mind that a miracle is a violation of the laws of nature, and so the evidence we have against miracles is the overwhelming weight of evidence for laws of nature themselves. Mackie considered various takes on the claim that reflection on the idea of God leads to proof that God must exist. You might argue that if God is defined as the greatest conceivable being, and if it’s greater to exist in reality than just in thought, then God must exist.

“‘There are no objective values,’ Mackie wrote. He was not one to waste opening lines”

Called the “ontological argument,” this line of thinking has convinced many. But by this reasoning, we can define all sorts of ridiculous things into existence—how about the Greatest Conceivable Island? Where’s that?

He considered proofs characterising God as the uncaused first cause or as the necessary presupposition of morality, and found them wanting. He also looked at the old idea that the design witnessed in all creation is a sure sign of a designer—but by the same logic, doesn’t the designer’s mind need designing too? Mackie didn’t think any of the arguments were conclusive, or even persuasive, but it’s his treatment of the  problem of evil that stands out. With that, he said, sceptics “need not limit themselves to resistance: they can go over to counter-attack.”

JL Mackie. Source: Wikimedia Commons/Beretta Online

The problem is inconsistency. If God is all-powerful and perfectly good, how can there be evil in the world? “Why do the wicked live, reach old age, and grow mighty in power?” Job had a point, but it’s not just evil people. Why are there hurricanes, cancers and poisonous plants? How can all that be reconciled with the existence of someone who’s powerful enough to fix things and who’s entirely good? Mackie’s treatment of the moves and counter-moves, with his focus on the free will defence, is that rare thing in philosophy: a page turner. The problem of evil is not a conclusive disproof of God’s existence, but it leaves us with “the strong presumption that theism cannot be made coherent without a serious change in at least one of its central doctrines.” Close enough.

His scepticism about the objectivity of ethics went a lot further. He argued against the idea that moral values like goodness, rightness and wrongness, duty and so on are “part of the fabric of the world.” On the objective view, being good is a property a person or an action might really have. Slavery, itself, is evil. But for Mackie, there were no values out there to be had or to discover—ethics is invented, not encountered. Before you say no one really thinks morality is part of the external world, Mackie pointed out that objectivity in morality is “the main tradition of European moral philosophy.” He found expressions of it in Plato’s Forms, Aristotle’s notion of the good, and Immanuel Kant’s categorical imperative. But it’s part of everyday morality too: “although most people in making moral judgements implicitly claim, among other things, to be pointing to something objectively prescriptive, these claims are all false.” Strong stuff. Why did he say it?

“Objective morals would be metaphysically weird if they did exist”

His best reasons have to do with how metaphysically weird objective moral values would be if they did exist. They’d be “entities or qualities of a very strange sort, utterly different from anything else in the universe.” (This might commit us to the unlikely existence of moral particles, which the philosopher Ronald Dworkin helpfully called “morons.”) How could these things, whatever they are, interact with the ordinary natural stuff which makes up everything else? Worse, if the universe had such bizarre things in it, wouldn’t we need some equally bizarre faculty in order to perceive and know them? Something completely different from our ordinary senses. What could possibly fit the bill?

There’s a lesson here for people like us, living in polarised political times. A little scepticism about the objectivity of our values, the realisation that right and wrong might be invented, not set in stone, could help us stop butting heads. As Mackie put it, the first step past an impasse comes when opposing sides see each other’s differing descriptions of what’s going on as all making a kind of sense. “A second, harder, but necessary step is made if they can each see some force in the opposing point of view, that is, give some weight to the values and ideals that underlie the aims of their opponents.” 100 years after his birth—and 35 years after his death—a little of Mackie’s thinking might go a long way in Brussels and Washington.