About half an hour before the end of Alejandro González Iñárritu’s “Birdman or (The Unexpected Virtue of Ignorance),” our hero, Riggan Thomson (Michael Keaton), walks out of a cheap liquor store to the sound of someone declaiming, with monotonous vehemence, Macbeth’s famous “tomorrow” soliloquy from Act V of Shakespeare’s play. As Riggan walks down the street taking pulls from his bottle, he passes the bum speaking the speech, and the bum notices him passing, and calls out to him – “Is it too much? It’s too much, isn’t it? I’m just trying to give you a range . . .”

The line is a call back to a moment near the beginning of the film. Riggan is the director and star of a play (which he wrote), adapted from the famous Raymond Carver story, “What We Talk About When We Talk About Love.” But twenty years before, he was a huge movie star, most famous for playing a comic book hero, Birdman, in three installments of the eponymous franchise. This late-career theatrical outing is Riggan’s bid for artistic redemption – his way of proving that he can do work that matters, that is “important” and not just remunerative. That homeless soliloquizer’s line is a quote from the rehearsal of that play – it’s the last thing one of the other actors says to Riggan when he sees Riggan’s disappointment with his over-the-top line reading. Next thing that happens, a light falls on the actor’s head, and he’s out of the show – an accident that Riggan is convinced he caused, using Birdman’s powers of telekinesis.

It’s almost a throwaway moment, but in a way it’s a synecdoche for the entire film, its method and its message. Macbeth was kind of Shakespeare’s Birdman, when you think about it: a hero with quasi-magic powers capable of chopping foes in half with a single blow. And this speech, by a murderous tyrant learning of his wife’s death, is about the death of feeling: feeling like you’re just an actor, walking through a part. You may make a lot of noise, but it doesn’t mean anything; knowing that, you feel nothing at the passing of the only person you ever really loved. But, of course, that speech has to be delivered by an actor – and, as it happens, it’s a really hard speech to deliver convincingly, to deliver not as a “speech,” but as something genuinely felt. And it’s not just because the speech is famous; I suspect it has something to do with the double-consciousness the actor must have at that moment, that to be in that moment, he must be out of it, using the feeling he has when he thinks about what on earth the point is of what he is doing, right then.

And that double consciousness is what “Birdman” is most fundamentally about.

That’s not all, of course. On one level, the film is just an exquisitely snarky showbiz satire, something to be watched alongside “State and Main,” “Barton Fink” and “The Player” – and that might be readily deflated by “Sullivan’s Travels” – and on that level it’s a whole lot of fun. The key supporting performances, by Ed Norton as a “method”-mad stage actor, Naomi Watts as his vulnerable co-star and lover, Emma Stone as Riggan’s pouty daughter and assistant, Andrea Riseborough as Riggan’s own lover, and Zach Galifianakis as Riggan’s put-upon lawyer, are all poised perfectly on the knife-edge between outright satire and emotional realism – they are exaggerated for exactly the right amount of effect to make us laugh without ever letting us distance ourselves completely. Only Amy Ryan, as Riggan’s ex-wife, plays her part without a hint of show – a choice which I’m sure was deliberate, as it provides us with the necessary ground to read Riggan himself as a real person, and not merely the cartoon he so often sees himself in.

On another level, “Birdman” is just a self-conscious tour-de-force, Emmanuel Lubezki‘s bid to retire the cinematography Oscar once and for all – and, not incidentally, a clever argument-by-illustration for film as a medium in explicit contrast with theater. The illusion that 90% of the film is a single take is breathtaking simply as a stunt, but it’s also making a point – that film can make us feel like we are there, feel the same tingle at a flawless performance played out in real time that the stage can. But film can also keep us in a character’s world, in his mind, can give us a point of view in a way that the stage is not optimally suited to do (though there are certainly plays and productions that try – The Glass Menagerie comes to mind as an obvious example). We’re not “with” Riggan is comprehensively as, say, we are with Travis Bickle in “Taxi Triver,” but the world the film explores is overwhelmingly his, even when he isn’t engaged in literal flights of fancy.

But to take this comedy seriously for a moment, it’s about whether art, particularly the art of performance, matters at all. And, by extension, whether life matters at all, since all we are doing in our lives is playing one or another part, and the measure of artistic success in performance is whether it doesn’t read as a performance, but feels as real as life.

In this, as well as in its method, it reminded me of another film about making theater: “Synecdoche, New York,” Charlie Kaufman’s brilliant directorial debut, and the film that for a while looked like it might have ended his career. I’ve been meaning to write something about “Synecdoche” for a long time, and have managed only to allude to it – which I will no doubt do again, as it’s a very important movie to me. But “Birdman” helped me contextualize it differently – and see better the ways in which it’s telling a story that’s easy to mock, and how it might have benefitted (as “Birdman” has) from greater self-awareness of that mockability.

“Synecdoche” tells the story of mopey theater director Caden Cotard (Philip Seymour Hoffman). At the beginning of the film, he’s just staged a radical re-imagining of Death of a Salesman. (As with Carver in “Birdman,” the choice of material speaks volumes about the hero; but that’s a subject I’ve written about before.) His wife doesn’t like the play, which lets us know something is wrong there, and sure enough she leaves him almost immediately thereafter, taking their young daughter with her. Immediately after that, Caden gets a “genius” grant, and decides to use it to create the most comprehensive theater piece ever conceived: a theater piece that will contain the entire world, or at least the world of the creator and all he touches. For the rest of the film, Caden, in an abandoned warehouse, creates this work, hiring actors to play himself and the various people in his life – and then, as he descends further and further into his own work, actors to play the actors who, because of long association, have become important people to him in their own right. The work grows and evolves, but is never staged before an audience. It ends as a ruin of its once-fantastical self, with Caden’s own death.

Obviously, the conceit isn’t intended to be taken literally. Caden’s theater piece isn’t a real theater piece; it’s his life – the life of an artist who, perforce, creates art out of the materials of his life, and whose life over time becomes more and more dominated by that activity, increasingly populated not with “real” people but with people engaged with him in that same act of artifice. But that missing audience, ironically, becomes more powerful and awful if we think of it in metaphorical terms than if we take it straight. Taken straight, it’s a joke – this guy has spent his life creating a work of art, but who is it for? Nobody is watching! But taken as a metaphor for the artist’s life, it’s more terrible: this guy has been living his life, as an artist, but who has he been living it for? Is anybody even there?

And that, in turn, is the question “Birdman’s” Riggan asks at the end of his play, in a flashback to the scene of violence that Carver’s story refers to but doesn’t show: Ed’s bungled suicide. “I’m not even here; I’m invisible,” the character says – and then shoots himself. One of the delights of “Birdman” is seeing how this ending, and his play generally, changes with each performance, shedding new light on what it means for Riggan – just as one of the (far more elaborately developed) delights of “Synecdoche” is the repetition of scenes, first in Caden’s life, then on his “stage,” then riffing and transforming as Caden’s life moves on, and his art gets more and more tangled and impacted by that life.

I don’t want to give away too much about the ending of “Birdman,” but I’ll say this. Birdman himself, the character Riggan played and who follows him around for much of the movie taunting him in voice-over, has his own notions of what it’s all about: it’s about giving the audience what they want, and thereby becoming bigger than human, big enough to give them all of what they want. They want blood, they want excitement. You might say they want to know you love them so much you’re willing to kill somebody for them. That’s what the characters in the Carver story are debating. And that’s what, ultimately, Riggan gives them on stage.

And what about Caden? He has no audience. So why is he doing it? Where’s the love, even the twisted love, even what ultimately amounts to self-love, in the kind of art Caden is creating? Caden’s art is made out of his life, but it isn’t made for anybody. The deaths that happen in his world – there are two of note, one a suicide and one a comically foreshadowed accident – feel like extravagant attempts to get his attention, not ours. The solipsism of Caden’s world is so complete that the ending of the film recalls the Housman poem:

“Good creatures, do you love your lives
And have you ears for sense?
Here is a knife like other knives,
That cost me eighteen pence.

I need but stick it in my heart
And down will come the sky,
And earth’s foundations will depart
And all you folk will die.”

I don’t mean to dump on “Synecdoche,” which means a huge amount to me, or to build up “Birdman” to something bigger than it is. Part of the difference between the two films amounts to the fact that “Synecdoche” is ultimately closer to the consciousness of a writer, while “Birdman” is about an actor. Part of it is that “Synecdoche” has a much bigger canvas – a whole life, a whole world – and a much looser method. Both films play with the boundary between reality and cinematic or theatrical representations thereof, and both films also play with our sense of time and space, but “Birdman” holds a much tighter rein on its conceits.

But I’ve put these two films together as a double feature not just because they are doing certain similar or comparable things, but because they are very different in spirit, and consequently have something to teach each other. And what “Birdman” could teach “Synecdoche” is the unexpected humility of arrogance. “Birdman” knows that all it’s showing us is the life of a middle-aged movie star in all his pompous self-importance. It knows how we’re going to take him down a peg, and it gets there first. This makes Iñárritu’s film, on the one hand, seem more purely entertaining than Kaufman’s, which wears its pretensions to importance on its sleeve. But because the film has already taken Riggan down a peg, we’re free to actually identify, where Kaufman’s Caden actively pushes us away – one reason for its commercial failure, I suspect, is that only those already inclined to fear their own comprehensive solipsism were drawn in. “Birdman” is about absurd and willing victims of celebrity culture, and it doesn’t take their ambitions particularly seriously. But they take them seriously, and we’re free to let it ramify for us beyond the world of celebrity culture, to have it mean something to us.

“Birdman’s” range is, ultimately, as wide as you’re willing to let it fly.