Atheists and theists sometimes notice—or think they notice—the same irony in the legacy of atheist thought. “Isn’t it funny,” they ask, “that many great thinkers atheists look up to are deists?”

Many of the writers atheists admire are deists. Voltaire, Thomas Paine, and Mark Twain were all deists. All three also had insightful and funny religious criticisms that still influence atheist argument today. And that is ironic. But the irony is at the expense of the religious, not us.

Deism is the belief that a divine creator made the universe. However, that creator then let the universe run its course according to natural laws. The deist god doesn’t answer prayers or intervene in our lives. It just winds the clock and lets it run. Readers probably know what deism is. But they may overlook the biting criticism that makes deism so hostile toward traditional religious belief. Theists believe in a personal god that answers prayers and intervenes in our lives to answer them. Denying that there’s a god answering prayers is a direct challenge to religious dogma.

But religious figures often claim deists to their side. Deists believe in a god, and from there, it’s a small step to say there’s a personal god that answers prayers. But if the religious want to say that the prayers of those in churches and hospitals go unanswered, we’ll welcome that concession.

However, some Christians will co-opt deism to try splitting the difference between theism and atheism. These Christian deists may believe in the teachings of Jesus but reject his divinity. Again, that’s a massive step away from the type of god Christians have preached about for centuries. A god that doesn’t intervene in our lives doesn’t need submission from us either. If Jesus is being read as any other philosopher or thinker, then what’s the point of submitting to him? Claiming deists for the religious side challenges theism as directly as any atheist’s claims.

But Christians aren’t the only ones who attempt to split the difference between atheism and theism. The “spiritual but not religious” crowd does too. They reject theistic gods but insist that there’s “something” out there. They don’t specify what that something is. They don’t define the “something” that moves the universe or how it does so. Throwing terms such as energy or force around usually amounts to the same kind of bleating that Christopher Hitchens criticized the Christian flock for engaging in.

Both the religious and the nonreligious try to create a middle ground by pulling from some form of deism. But even if we allow deism’s belief in a creator, the creator’s lack of interest in us eliminates any middle ground the fence-sitters hope to find. If the creator can’t be reached through prayer, then why pray? If the creator doesn’t interact with us, then why try connecting with it? Splitting the difference raises unanswerable questions for believers and nonbelievers alike.

In fact, deism has a response to the middle-grounders. In his book Black Freethinkers, Christopher Cameron reminds us that deists didn’t have to connect with a higher power to gain a deeper understanding of the universe. Deists had to use their own minds and learn about the universe to connect with it. Their “spiritual” connection to the universe came from what they could learn about it. They didn’t rely on something outside of themselves to find meaning or significance.

So, deism dismantles the theist and “spiritual but not religious” hijackings. They’re forced to find meaning themselves instead of connecting with a “force” that will find it for them. Deism’s command to take responsibility for finding one’s own meaning is a direct challenge to New Agers and traditional Christians alike.

However, that doesn’t mean it challenges atheism. Astronomy, cosmology, and physics have rebuffed deism’s central belief. We didn’t have the big bang theory until the 1920s, much less the advances in quantum theory that explain how particles can appear and disappear seemingly from nothing. These discoveries by themselves don’t disprove the idea of a creator. But they allow explanations for creation that work without a deity. With everything we know about the natural world today, belief in deism amounts to an admission of a lack of imagination.

But for people who want to cling to some spiritual truth, atheists have profound things to ponder too. In 2019, organic chemist Thomas Carell simulated the early Earth conditions that led to the creation of the four nucleotide bases that make up RNA.

In layman’s terms, he may have discovered the origin of life.

In previous experiments, he’d been able to create two of the four RNA bases at a time. But it took him over a decade to simulate the environment of Earth’s early days that would create all four nucleotide bases at once. This would lead to the formation of RNA, DNA’s precursor. Carell found a pathway to life, not only cementing the idea that we don’t need a creator but also giving further credence to the idea that we’re not alone in the universe. His work’s implications are astonishing to think about.

In the light of discoveries such as those, it’s easy to see why atheists cut their forebears so much slack. We can intimately study the origins of Earth, the universe, and life itself with technology Thomas Paine couldn’t have dreamed of. Inserting a creator where it didn’t belong was the first proposed answer to how we got here. Belief in that creator was also mandated by force for centuries. By rejecting that creator’s interest in humans, deists rejected centuries of religious dogma. They were the original radicals.

But today, we have new avenues of wonder and belief to explore. Scientists from all disciplines not only inch closer to important answers, but they also discover new questions to encourage new avenues of research. We don’t need holy books to discover the transcendent. The world around us, our knowledge, and the universe contained in every human being can fulfill that.

When the religious claim deists for their side, we should be happy to let them try. If the religious want people who don’t believe that prayers work or that a god can be petitioned for a favorable place in the afterlife to speak for them, then by all means let them have them. Deists make many of the same criticisms of religion that atheists do because they don’t believe in a personal or intervening god either. That’s why they’re such important figures for us, and that’s why we shouldn’t be afraid to embrace them.