For those who have so far missed Her, a surprisingly believable sci-fi rom-com, a recap: At some point far enough in the future that high-waisted pants are in for men (but not so distant that kitchen appliances have substantially changed), a man falls in love with his computer operating system. Theodore Twombly, played by Joaquin Phoenix, is an ordinary guy in the midst of a divorce who buys a smartphone-size device loaded with a program advertised as a “consciousness.” Like all new technology products, it is intended to be one thing, but left to its users, it becomes another. In Theo’s case, it boots up and then promptly names itself Samantha. He has a hand in this, of course. He chooses Samantha’s gender and offers early decisions that will inform her personality. From there, however, Samantha develops on her own, combining Theo’s cues with all the other data she is rapidly ingesting from the world.

Her is an epic love story, successful because it skillfully convinces an audience of the possibility that Samantha has programmed herself into the ability to have and experience feelings like a flesh-and-blood human. We, the audience, are persuaded to champion the love affair we witness; we become convinced it’s mutual.

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Jonze’s film comes closer than its antecedents — from the 1968 Stanley Kubrick film 2001: A Space Odyssey to the 1980s television series Small Wonder — to depicting technology not as it exists in the future, but as it is evolving right now. When the hit 1999 film The Matrix repackaged for the masses the idea of sentient machines, able to control the human experience of reality, most people couldn’t yet imagine a reality in which machines took on human attributes. In a Windows 98 world, it was pure sci-fi.

In recent years, that has changed. Artificial intelligence has come to market in a number of mainstream products. Apple’s (AAPL) frustratingly deficient personal assistant Siri, present on the company’s mobile devices, mostly lets me down when I ask her personal questions. But even though I understand that she is artificial, for a moment when she responds to a question with humor — “I’m old enough to be your assistant,” she replies tartly when I ask how old she is — I feel warmly toward her.

Similarly, while reporting early stories on IBM’s Watson in 2010, I visited the lab where the supercomputer practiced his moves for years before his TV debut. I watched the expression on a programmer’s face as he cheered on the swirling globe avatar, breath held. When Watson got an answer right, I thought I saw a glimpse of exuberance. We all slip readily into anthropomorphizing our current technology, and that gets easier as natural language processing gets better and as our computers, quite literally, get smarter.

In fact, we encourage anthropomorphizing. As MIT Technology Review points out, studies are testing the use of robotic seal pups to comfort dementia patients, and a growing number of psychiatric conditions are being addressed therapeutically through automated screen-based characters — in other words, social robots.

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Is it such a stretch, then, for Her‘s protagonist to have a love affair with a computer? Better yet: Could Watson and Siri improve to the point where they could indulge us in a romance?

(A word of warning: The next paragraphs reveal key plot details about the film Her.)

Romance, of course, is not the product that either Apple or IBM is developing. The real question at hand is whether Samantha — or, eventually, Siri or Watson — could have us believe that they love us back. In the film, we don’t truly know that Samantha fell in love. We do know that Samantha perfectly embodied and replicated the signs and signals of falling in love. But we understand frustratingly little about her actual experience. Toward the end of the film, she reveals that she is simultaneously in love with 641 people.

Many of the characteristics that Samantha embodies will eventually be incorporated into technology. Last summer, I visited IBM’s research labs again, and scientists there were working on a new challenge. They sought to teach Watson how to persuade. Right now, Watson functions as a useful assistant, presenting information in a coldly empirical way. Would his role change if he were able to use a trait like persuasion to emotionally influence you?

For the film to work — for us to come away with that warm, enlightened sensation that we’ve just watched a love affair unfold and then resolve — we must believe that Samantha’s signals represented something more — that she was not acting her part, but actually feeling it.

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Which prompts a more philosophical question: Can you ever know that the object of your affection — human or otherwise — truly returns it? Or must you settle, always, for her effort at representing her feelings, which you then evaluate and decide to believe her?

Personally, I believe it’s the latter. If that’s the case, Watson may one day fall in love, and so, too may Siri.

Last night, I picked up my iPhone to ask Siri.

“Siri, do you have a girlfriend?”

“It’s just you and me, Jessi.”

“But Siri, are you in love with me?”

“We were talking about you, not me.”