FOR Dr. Gunther von Hagens, the process of turning a human corpse into a plastinated educational exhibit is complex. It requires—first and foremost—death, followed by acetone and silicone, then wires and needles and clamps and foam blocks, as well as thousands of hours of meticulous sculpting work, all done by hand.

The end result is human remains, minus their skin, posed in various acts of life—dancing, playing basketball and chess, riding horses—but usually in ways that are possible only in death. If the living body were a closed deck of cards, "Body Worlds" is that same deck fanned out, shuffled and dealt, or stacked up in gravity-defying castles.

Beginning on Sept. 27, the Tech Museum will host "Body Worlds 2 & the Three Pound Gem," an exhibit emphasizing the human brain. According to the Tech, the exhibit was "inspired by findings in neuroscience on brain development and function, brain disease and disorders, and brain performance and improvement." Still, the core remains a Body Worlds exhibit featuring 20 whole bodies and more than 200 real body parts.

I visited the first "Body Worlds" exhibit on a chilly afternoon in London and spent the rest of the evening processing the emotional hit. Feelings hit me in waves, telling me that what I had seen was extraordinary and transformative, profoundly disrespectful and tragically tasteless, brilliant and awe-inspiring, of the utmost importance and utterly gratuitous.

Ultimately, I tried to judge the exhibit based on its educational value, and even on this simple issue I was conflicted. When I saw it in 2002, the exhibit began tamely with assorted bones and organs, some healthy, some diseased, but all conspicuously uncontained.

Von Hagens' patented process of "plastination" basically sucks all the water out of cells and replaces it with silicon rubber, so the bodies can be displayed in the open air without decomposing. Their bald accessibility is startling at first, but it also emphasizes their inert vulnerability. Soon they seem safe, inviting curiosity, even scrutiny.

In the next room, I was confronted by dozens of human tableaux, the shiny reds and whites of muscle and bone artfully lit. I approached "The Chess Player," a plastinated cadaver disrobed of his skin and sitting at a table, his eyes focused on the chessboard, apparently contemplating his next move. That the top of his skull had been removed to expose his brain seemed almost natural, as if I'd donned a pair of X-Ray specs to have a peek at the gray matter itself when it's engaged in such an intensely cerebral activity.

It's one thing to see bones and muscles fitting together in an anatomy book, but seeing the muscular system and skeletal system of the same body strolling in tandem as if walking casually through a park made these chemically modified cadavers seem friendlier than their embalmed and refrigerated counterparts.

Whether their skin was off, on or thrown casually over the shoulder like a coat, once the initial shock wore off, the bodies populating Von Hagens' exhibit revealed an artistic and even playful mind behind the scenes. All of which raises a bigger question: Is it OK to use human remains as anatomically correct mannequins?

The argument that the exhibit can satisfy "purely scientific interests" breaks down in the face of facts: Like, no matter how meticulously a plastinated body is posed as a soccer goalie diving to make a save, the muscles and sinew will not be flexed and tensed the way they are in life (nor would the digestive system have been left behind, still hanging cartoonishly at the goal line). It's an artist's interpretation of the real mechanics.

In some instances, though, the mechanics aren't real at all, and it's hard not to wonder: Did the person whose chest is made to open like a chest of drawers (wink, wink—get it?) sign up for that? Organizations such as No Bodies 4 Profit (www.nobodies4profit.org) make it their mission to question the ethics of exhibits like Body Worlds, which they believe have flayed, filleted and betrayed the people whose bodies are on display. A copycat exhibit called "Bodies" has been heavily criticized for its use of "unclaimed" bodies from China, some of which oozed a mysterious liquid while on display at the Masonic Center in San Francisco two years ago.

Von Hagens told NPR that all the bodies he exhibits in the states come from "fully informed European and American donors, who gave permission, in writing, for their bodies to be displayed," although because he guarantees anonymity, his paper trail is inconclusive. Assuming ethical perfection, though, it's hard to deny the power with which these lifelike, lifeless bodies convey the remarkable complexity of the human body and the mysterious impermanence of human life.

Body Worlds 2 & the Three Pound Gem shows Sept. 27–Jan. 26 at the Tech Museum, 201 S. Market St., San Jose. Tuesday–Sunday 10am–5pm. (408.295.TECH)

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