The "hard problem" of this play's title refers to the very nature of consciousness, and spoiler alert, Tom Stoppard — a playwright whose beloved Arcadia and Rosencrantz and Guildenstern Are Dead have masterfully illuminated that timeless question — hasn't come any closer to a solution with his latest work. That may be because The Hard Problem, which is in its West Coast premiere at San Francisco’s American Conservatory Theater under the direction of longtime Stoppard collaborator Carey Perloff, is unsure if it's a drama or a morality play, poring over somewhat tired philosophical problems and psychological studies from the prisoner dilemma to the Milgram experiment rather than fully dramatizing or complicating them anew.

Hilary, a psychology student who applies to and later joins the elite Krohl Institute, is at the center of the drama. Though she's played with heart and humor by Brenda Meaney, the character is more symbol than flesh and blood, and as such it's hard to care too deeply about her. Raised Catholic, Hilary gave up a girl for adoption while in high school, and her staunch belief in God and related desire to prove an innate goodness in people is reduced to a hope that her child has been raised well and is happy.

Hilary's worldview is pitted against that of her instructor and lover, Spike (Dan Clegg), and even more than she, Spike is stand-in for a belief system. Yet he, at least, is open about it: "I'm Darwin," he declares, cleverly nodding to his character's function, "I'm Mendel. I'm Crick and Watson. I stand for all the science that's taught." Still, most of the theatergoing crowd isn't going to find his unwavering faith in evolutionary biology as an explanation for consciousness to be very compelling, so Spike is a straw man. So are other characters, like Hilary's rival for a spot at the Institute, mathematician Amal (Vandit Bhatt), though he's a bit more fun because he doesn't seem to really care if he's right or wrong, and Bo (Narea Kang), her assistant and Amal's love interest, is also a bit more interesting, though a motivation for her behavior provided late in the play feels weird and forced. Jerry Krohl (Mike Ryan), the founder of the Krohl Institute and a hedge fund manager using the Institute's findings to understand markets and traders, is also somewhat complex — maybe just because he's given more dramatic function. Ryan plays him brashly and well, and his scenes with Hillary were my favorite.

Andrew Boyce’s set design is very functional and cinematic — the Krohl Institute is sleek and believable, for example. Bedroom scenes, though, feature an illuminated screensaver-looking backdrop — there are clouds, flowers, and ripples — and although it's pretty and not distracting, it did exacerbate the play's confusion between the symbolic and the real.

The crux of The Hard Problem is a dramatic coincidence — or merely an incidence — that's supposed to make believers of the audience, and it succeeds in being touching. But a central study in the play — Hilary's big coup, an experiment based on the Milgram one, is really muddy. A group of test subjects supposedly un-learns empathy as they grow older, which Hilary weaves into a defense of God (we're spared the specifics).

Stoppard's ability to stage academic discussions onstage is undoubtedly special — see Rock and Roll — but it's not at its best in The Hard Problem, which one might guess kept the latter play from receiving the Broadway run that most, if not all of Stoppard's recent plays have received. At the end of the play, Hilary decides on a new course of study — philosophy proper, with no staged experiments or practical applications necessary. The play itself might have taken her cue.

The Hard Problem runs through Nov. 13, at A.C.T.’s Geary Theater