Is there such a thing as the human soul – and if so, is it something substantial that can be weighed? Pondering that question, Dr Duncan MacDougall set out to find the answer at the beginning of the 20th century, in a series of experiments that would have no chance of passing ethical boards in the modern day. MacDougall weighed six different patients in the process of dying from tuberculosis on an industrial sized scale. His surprising result: that, at the time of death, the scales measured (on average) 21 grams lighter.
A recent article on the Fortean Times website (“Soul Catcher“, by Paul Chambers, originally from Fortean Times #262) outlines the story of Dr Duncan MacDougall, and ends with the summation that the experimental results are largely worthless:
MacDougall’s correspondence reveals a man with an unswerving belief in the existence of a human soul. At every turn he sought to justify his results in these terms, dismissing or ignoring any evidence to the contrary. It is, for example, possible that he ignored the results of the sixth patient because, in his own words, “there was no loss of weight” measured at the time of death. MacDougall explained in a letter that the negative result was probably due to the patient having been on the scales for only a few minutes, which caused him to doubt “whether I had the beam accurately balanced before death”. This seems like an afterthought used to explain an inconvenient result and one wonders what his reaction would have been should the result have been favourable.
This is hardly a shocking conclusion – MacDougall’s methods have come under regular criticism since his anomalous results were published. Explanations have ranged from lack of control of moisture loss to air convection and vibrations from breathing and heart palpitations.
Coincidentally though, the recently-released Spring 2010 issue of the Journal of Scientific Exploration (24:1) has an article from Masayoshi Ishida rebutting a number of the claimed refutations of MacDougall’s experiment. Here’s the abstract:
A critical review was conducted on criticisms expressed in books and on websites of Duncan MacDougall’s weight measurement experiment upon the death of terminally ill patients; theoretical simulations of MacDougall’s experiment using a modern weighting system with load cells and thermohydraulic analysis were employed. The following conclusions were obtained: (1) the uncontrolled escape of moisture from bodies due to insensible perspiration has practically no effect on the conclusion of his experiment that there had been anomalous losses in the weight of his patients upon death; (2) the speculated effect of convection air currents on MacDougall’s balance scales does not exist; (3) vibrational disturbances caused by cardiac and breathing activities, which disappear after the death of the patients, have practically no effect if the change in weight upon death is in the tens of grams rather than a few grams; and (4) the speculative tricky role of buoyant force of air on the body can be denied. Therefore, all the cases of his experiment do remain as pioneering cases published in a scientific journal. Theoretical implications of his experimental result and future perspectives of the experimental approach to this subject are discussed.
I do have to say that I think Ishida shoots his article in the foot somewhat by including some discussion of channeled information from ‘Seth’ in the final section on the experimental approach. While it does relate to the subject matter (whether correct or not), this mention means that no orthodox scientist is likely to take the rest of the article seriously.