DURHAM — For at least 100 years, the more oddball branches of science have struggled to answer this metaphysical head-scratcher: How much does the human soul weigh?

In 1907, a Massachusetts doctor named Duncan MacDougall settled on the figure of 21 grams – the average weight loss experienced by six terminal tuberculosis patients he strapped to a scale at the moment of death.

A dozen years ago, an Oregon rancher named Lew Hollander tried to measure the souls of one ram, seven ewes, three lambs and a goat. His findings: The animals actually gained weight as they shook off this mortal coil – anywhere from 18 to 780 grams.

Now this summer, the Rhine Research Center in Durham will host the latest experiment aimed at nailing down the intangible essence of mankind.

The method: 1.) Stand on a scale. 2.) Have an out-of-body experience. 3.) Record weight.

“We want to have irrefutable evidence to present to the scientific community,” said Jerry Conser, a Dallas oil man and psychic researcher who came up with the idea. “We’re going to have a hurry-up, quick-and-dirty series of experiments. If we can show consistently and repeatedly that every time somebody goes out of body, there’s a corresponding weight change ...”

I’ll finish the sentence. It would be awesome.

The Rhine Center, named for the psychic research pioneer J.B. Rhine, is famous for probing into the world of unexplained phenomena: ESP, near-death experience, poltergeists.

Rhine himself was best-known for his ESP queries, including one that involved a mind-reading horse named Lady Wonder. But he also dabbled in the geography of man’s inner identity, penning an article in 1946 entitled, “Scientific Evidence Man Has a Soul.”

Conser, 67, heads a like-minded group, the Psychical Research Foundation, and about eight years ago, he was puzzling over past attempts at nailing down soul weight, wondering, “If you can’t do it with dead people, how can you do it?”

Then he thought of another group: the Monroe Institute in Virginia, where you can actually take classes on how to have an out-of-body experience.

Monroe has people in its ranks who are so skilled in soul traveling that they can depart this Earthly realm more or less whenever they please. These out-of-body frequent-fliers will conduct the experiments at Rhine sometime in the next 90 days, leaving terra firma six times in the span of a weekend. As a bonus, Conser plans to weigh subjects with the same digital scale that Hollander used on his sheep.

“If we see a weight change, we’ll do a full-blown, several-years study,” Conser said. “It’s going to be such a controversial and dramatic research project if it’s a success that you better have all your ducks in a row.”

I asked Conser to describe some of his own out-of-body experiences, and he graciously agreed, though it’s not as vivid a depiction as I’d hoped. I imagined soaring over the Himalayas, arms outstretched Superman-style, but that’s a cartoonish distortion of the real thing.

It gets complicated, but you travel through various domains, the first being total darkness, the next a kind of horror-show filled with souls who can’t let go of their Earthly lives, progressing all the way to paradise. You don’t just close your eyes and ... poof. Soul travel takes a lot of work.

But whatever the soul is, Conser thinks mankind can get to know it better, analyze it, examine it, record it as data. He’ll be waiting at the scales, pen in hand, eyes wide as the mysteries of the universe unravel.

jshaffer@newsobserver.com or 919-829-4818