No one makes me laugh like my big brother. We’ll be Skyping across the world and I’ll be heaving and drooling, my entire body convulsing, my face contorted. And I love it. It’s rare to laugh like that. As I’ve gotten older — I’m 45 —, I find I’ll say, “That’s so funny,” while barely breaking a smile. Oh, to laugh fully demands a kind of surrender, succumbing to the world, letting go of ego and propriety as you grunt, wheeze, drool, and fart.

How and when we laugh is not frivolous, something that might be nice but is somehow inessential. On the contrary, in the things we find funny (or not), lurk entire worlds.

I’ve been obsessed with irony for a long time. It’s the topic of Kierkegaard’s dissertation, not surprisingly entitled, On The Concept of Irony with Continual Reference to Socrates — which, for the record, is hilarious if you’re into that kind of thing. He had to ask for a special dispensation to write his thesis in Danish, not the usual Latin, so he could play ironically. In it, he makes these wry jabs at key academics and such. Which, of course, he delivers ironically.

Irony has been the figure of resistance for millennia. I can tell the king I respect him while meaning something else entirely — and even signal to others that I don’t really mean what I say. Irony can maintain my personal integrity — I’m not really saying I like the king — while also establishing a community of dissent as others detect my tone. Richard Rorty claims that this is in fact how irony functions: by building complicity among a certain crowd (a minor crowd, as Deleuze and Guattari might say).

A lot of comedy is premised on irony. In a recent episode of “Scandal,” the indefatigable Olivia Pope is kidnapped and imprisoned in some secret place, presumably Sudan. She grabs her cell mate, looks him in the eye, and gives an impassioned speech that she is Olivia Pope, damn it, and that means she will be safe, saved, rescued. She then realizes the absurdity of her claim, laughs, and says, “It’s funny because it’s not true.” Indeed, the humor — what there is of it — lies in the radical discrepancy between her known world and the new world in which she finds herself, namely, a world that doesn’t give a shit about Olivia Pope.

Irony posits two realms: the eternal, or divine, and the temporal, mortal, physical. We live in this world with its laws and constraints, its culture and bodies. We think certain things which are defined by words, habit, power, desire, need. But we know there is another world that exceeds this one and that in fact fuels this one. This is the plane of pure Being, of Life itself, that blurs boundaries and makes such silliness of our all too human world.

As Kierkegaard argues, Socrates was the king of irony. His philosophy is premised on the belief that the only thing we know is that we know nothing. And so he goes about Athens pestering people who claim to know until said people either walk away or admit they know nothing. Which is why Socrates speaks ironically: he lives in this world while pointing to the other world. (This is why Nietzsche considered Socrates a nihilist: Socrates isn’t happy until everyone claims to know nothing.)

Recognizing that there are these two planes, we adjust our language accordingly and speak in two registers at the same time, an odd kind of self-harmony (although quite different than the Tibetan monks throat singing or Roland Kirk’s flute playing grunting scat). This dual-register articulates the needs of this world — its laws and desires — while pointing to other world, to an Eternity that effaces all our laws and bodies. It lets us be human while recognizing the divine.

Humor posits a different relationship between bodies and being, this world and that world, life and ideas. In this world of humor, the two planes are not conflated per se and yet they are not radically separate, either. They infuse each other, inflect each other, are intertwined. The mockery of this world by that world — and vice versa — is pervasive, thorough, and mutual.

If irony keeps things apart, humor conjoins them without unifying them. Irony is premised on either/or, the incommensurability of the finite and the infinite (and the title of Kierkegaard’s great book). Humor is deployed via and. It’s not that bodies and ideas are one and the same; it’s that the terms of their relationship lack discretion, are multifarious, and delirious. As Deleuze argues, Kierkegaard is a leaper, jumping between worlds separated by either/or. Nietzsche, meanwhile, is a dancer, flowing along the undulating surface of becoming. This is the difference between the comedy of irony and humor: irony jumps, humor dances.

“Seinfeld” gives us irony and humor side by side. Jerry is ironic. He maintains his place in this world while realizing its absurdity. Kramer, meanwhile, is humorous: in him, the different planes of existence meet and play out their odd relationship. We see Kramer become a dog, a pimp, a karate expert. His whole being is consumed by the transcendental plane of becoming. Kramer never knowingly winks, never signals that he knows nothing, never points to the Eternal. While Jerry presents his ego while pointing to its undoing — the premise of his stand up comedy—, Kramer’s doing and undoing is commensurate with his ego. Kramer is not a comedian: he is humor happening, the and of becoming — man and dog, man and pimp, man and x.

Jim Carrey is not ironic; he’s humorous. Like Kramer, his whole being commits to the transcendental plane as it becomes a local expression of other worlds. He doesn’t slyly point elsewhere the way, say, David Letterman does. I always saw Letterman as the modern day Socrates, taking on the silliness and vanity of so-called stars. This is what lies at the heart of Letterman’s shtick: all this — these movies, this TV, all of it — gives way because there is another world that’s true, that’s essential, that’s transcendent. Carrey, meanwhile, lives the madness, the delirium, of that transcendental world here and now. He never points elsewhere. It’s all going on right here.

So what of my hysterics while Skyping with my brother? On the one hand, it’s the madness of this world giving way to another world. Isn’t that what siblings do for us, do to us — remind us that despite all our grown up pretensions, our quoting of Deleuze, our fancy jobs, we’re really just silly kids, that life is either/or? On the other hand, siblings have that incredible ability to link these two worlds, to fold the beautiful humiliations of our childhood into the humiliations of our grown up selves and, I suppose, vice versa — to be the and. When I laugh with my brother, a laugh resonant and thorough, I am simultaneously drunk on irony and humor, my different selves at once discrepant and intertwined.