Spoilers ahead.

The website WikiHow offers 11 pieces of advice on "How to Avoid Uncomfortable Conversations About Religion." These include "resist the urge to argue," "state an assertive personal policy," and "redirect the conversation." Which are useful tips—and also not too different from the actions you're supposed to take should you, on the course of an otherwise pleasant hike, encounter a bear.

Avoid the religion talk. As a social commandment, it has become cliche for a good reason: When religion is both plural and political, conversations about it can indeed become "uncomfortable." And the discomfort can translate not just to the conversation, one of the smallest mediums we have, but also to one of the most massive: the Hollywood film. With a few exceptions, among them Darren Aronofsky's Noah and Ridley Scott's upcoming Exodus: Gods and Kings, major studios have avoided religion as a topic for its big-budget films. After a period of brief investment in them, the Wall Street Journal noted of Christian-themed genre movies, the industry's enthusiasm has "faded."

That makes commercial sense: The movies that have the best chance of succeeding at the box office, if not among critics, are the ones that appeal to the widest possible audiences. A film that expressly deals with a religion, be it Christianity or any other, is rare for the same basic reason that WikiHow offers 11 different ways to extricate yourself from Godtalk: It can be divisive.

The problem is, though, that religion offers rich terrain for cinematic exploration. It provides, on top of everything else, the same themes that have inspired artistic creators for centuries: mythology, memory, mysticism. So filmmakers have developed a canny way to talk about religion in movies without actually, you know, talking about it—allowing themselves to explore the biggest of life's questions and ideas while avoiding "Uncomfortable Conversations."

Their method involves a political safe space: space itself.

Space epics, the ones that have ambition beyond classic action (Star Wars) and adventure (Armageddon), concern themselves, almost by default, with metaphysics, questioning the how and the why and the what ifs of the world and the space beyond it. There's Kubrick's 2001: A Space Odyssey, with its lauded ambiguities of spirituality and existentialism. There's Zemeckis' Contact, whose Palmer Joss (played by one Matthew McConaughey) is essentially an allegory of religious faith in the face of other approaches to the world. There's Shyamalan's Signs (with Mel Gibson in the role of the allegory). There's Scott's Prometheus. There's the "metaphysical head trip" that is Cuarón's Gravity. These films treat space not just as a spectacular setting for a story, but as a question to be answered. They deal with religion not just as a human institution, but also as something broader and more universal: a vehicle for human spirituality.

The latest to explore the spiritual implications of space is Hollywood's reigning philosopher-poet, Christopher Nolan, and his reigning philosophy-film. While Interstellar, as one review put it, "never entirely commits to the idea of a non-rational, uncanny world, it nevertheless has a mystical strain, one that's unusually pronounced for a director whose storytelling has the right-brained sensibility of an engineer, logician, or accountant." Or, as Slate summed it up: "For the first time, Nolan’s universe has a God, or something like one."

That something is the "they," the mysterious creatures who communicate with Earth-bound humans, and who help to rescue humanity from a planet that has become, gradually and then suddenly, inhospitable. (Put another way: Salvation requires humans to have faith in the power—and the benevolence—of a being they can neither fully know nor fully understand.) "We used to look up at the sky and wonder at our place in the stars," Matthew McConaughey's NASA-recruited pilot, Cooper, laments early on in the movie. "Now we just look down and worry about our place in the dirt."

Interstellar's plot hinges, both intermittently and overall, on self-sacrifice, on characters willingly enduring death so that humanity as a whole might live. It hinges, even more explicitly, on the tentative promise of Cooper's return to Earth—what you might also refer to as a second coming. It features a chosen one (Cooper's daughter, Murph) and a chosen people: humanity as a species. There's a ponderous shot of Cooper, about to pilot his space-colonists into a wormhole, with his eyes closed and his hands folded in what is hard not to see as prayer. There is Hans Zimmer's booming soundtrack, the most prominent instrument of which is the organ of London's Temple Church. If you wanted to be Miltonian about itParadise Lost did take place in an interplanetary setting quite similar to Interstellar's—there's also a fallen angel in the person of Dr. Mann (yep, Dr. Mann), the brilliant scientist who, it is repeated several times, represented "the best of us" before he came to represent the worst.

There's also a lot of talk of good and evil. There's a lot of talk of faith. There's a lot of talk of love—love that is explicitly not romantic (Interstellar is as asexual a blockbuster as you'll find), but that is, in its best manifestation, selfless.

None of which is to say that Interstellar is a Christian—or even a religious—film. It is not, and this is the point. The "they" is not necessarily a metaphysical being; Zimmer's organ was chosen, he has said, for "its significance to science." Good and evil, faith and love—these ideas, of course, extend far beyond religion.

What it is to say, though, is that Interstellar, like so many space movies before it, has adopted the themes of religious inquiry. The scope of space as a setting—the story that takes place within the context of the universe itself, across dimensions—has allowed Nolan, like so many filmmakers before him, the permission of implication. Nolan has said that one of his primary artistic influences is the postmodern author Jorge Luis Borges; you can, indeed, read Interstellar, in the most generous interpretation, as you would any complex piece of literature. As Stanley Kubrick once said of the film that is the most obvious antecedent to Nolan's:

You're free to speculate as you wish about the philosophical and allegorical meaning of the film—and such speculation is one indication that it has succeeded in gripping the audience at a deep level—but I don't want to spell out a verbal road map for 2001 that every viewer will feel obligated to pursue or else fear he's missed the point.

Nolan is often accused of coldness when it comes to his characters; you could also argue that the fleshed-out personality is almost beside the point when your purpose is not just storytelling, but allegory. Nolan has, in his films before Interstellar, been best known for characters who struggle in introspective ways: with themselves, with partners, with the past and the future. They treat existence, and consciousness, as matters of internal opportunity and anxiety.

With Interstellar, however, Nolan has taken that microcosmic perspective and widened it to the dimension of the cosmic. The typically Nolanian questions—what does it mean to be conscious/responsible/loving/human?—here take on the heft of the human species as a whole. Interstellar is concerned less with "man versus nature" than it is with "man versus human nature." While the film has a marked admiration for science—it is science, in the end, that helps humanity to rescue itself—it has just as much respect for wonder and awe and what you might call, in the broadest and perhaps even the narrowest sense, faith. Its villains are the characters who trust too much in logic, without the ballast of something more transcendent. They are the ones who choose physical survival over everything else—who prioritize living, you could say, over life.

"It has been said," Carl Sagan wrote in Pale Blue Dot: A Vision of the Human Future in Space, "that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world." We are saturated, now, with images of space—not just from Hollywood, but from scientists. NASA offers an astronomy picture of the day. There are multiple websites dedicated to the sharing of "space porn." The images appeal not just because they are pretty, but because they are, in the most literal sense, awesome. They encourage us to think beyond ourselves, to question, to wonder. Sagan wasn't just an astronomer, but a philosopher-astronomer. Just as Christopher Nolan—and Stanley Kubrick, and Alfonso Cuarón—are philosopher-filmmakers. Space, speaking to us in its vast silence, brings out the philosopher in us all.