I don't know. It kind of can. At the very least, controlled studies have shown prayer to not work in regards to any measurable outcome. At all.
MY father when he was on staff at the University of Chicago Medical School (The greatest medical school in the world at the time.) says the staff consistently weighed a man in his bed while he was taking his last breaths. He died and at the time of death his weight went down one tenth of one ounce. Since there was no loss of fluids from the bed, it would appear that the human soul weighs one tenth of one ounce.
Prayer does work in some cases, but those cases always appear to be situations when individuals need to turn their whole lives around. I have seen that work hundreds of times in prison ministries, but people in prison usually are in most need of a reformation of their lives. I note that I have prayed to God hundreds of times asking to win Millions in the Lottery, and my prayer has never been answered. So, when one prays for things that God is not interested in providing, it fails one hundred percent of the time as far as I am concerned.
It was Dr. Duncan MacDougall of Haverhill, Massachusetts who attempted to weigh the human soul. In 1907, he placed 6 dying patients on a homemade scale, which also acted as a bed for the patients. He then recorded their weights before and after death. According to Dr. MacDougall, there was a difference of 21 grams between the heavier, living patients and their dead bodies.
He also experimented on 15 dogs and found no loss of weight between the living dogs and their dead bodies. He believed this was because animals do not have souls.
His experiments were criticized since of the six patients, two tests had to be discarded and the level of error was very high. Obviously, it was not a very scientific study.
In addition, no one has ever been able to repeat the result of these experiments. Basically, there is still no physiological evidence of the soul.
It's an urban legend propagated by a guy who did bad science - looking for an answer he already believed was true. Real science doesn't have attachments to pre-existing beliefs and values. It just observes and hypothesizes.
Why do people lose 21 grams of weight after death? | Answerbag