I gather we would have to differentiate exactly what we're talking about here.
There are a number of known physiological methods of inducing unconciousness (as opposed to just getting someone to submit due to pain).
These would include asphyxia (lack of oxygen due to choking or strangling), head impact (resulting in temporary "scrambling" of brain circuitry), shock (temporary anoxia due to the shock reaction causing blood "pooling" in the body's core), and various chemical substances, which can either suffocate (natural gas) or have an actual anasthetic effect. (ether, cloroform, etc.)
It seems that what we're talking about with all the above is on a different order; that is, the claim that the practitioner causes unconciousness by manipulating "chi" at certain pressure points, meridians, and so forth.
If the practitioner were able to consistently cause test subjects to lose conciousness due to his manipulations (or strikes, or whatever), we would have to determine if there was a physiological effect measurable by normally-used medical monitoring equipment. Is there a blood-pressure spike?
A sudden loss of BP? Fluctuations in blood glucose levels?
Degredation of the blood/oxygen supply? (anoxia)
Disruption of the normal brainwave pattern?
Disruption of the brain's use of glucose, or production (or non-production, or reception) or brain chemicals? (neurotransmitters)
All of this sort of thing could be readily monitored by normally available medical equipment.
If it's shown that a physiological condition occurs which might normally cause disruption of conciousness...We'd then be faced with the problem of assigning a cause.
If the claim is being made that the causative factor is Chi, then we'd have to design some method of demonstrating Chi, and showing that it actually exists. Note that at present, all the marvellous medical monitoring equipment we've developed has failed to show any evidence whatever of Chi.
The claim is sometimes made that Chi is so "subtle" that it can't be measured or observed. If that's the case, how can it do any work?
Gravity, on the local level, is remarkably weak. We have not yet directly observed the theorized particle, the graviton. Yet gravity is readily measurable and quantifiable with extreme accuracy. It's effects are readily apparent.
If one is going to demonstrate Chi in a scientific sense, the usual protocols would apply. Some description of the force, it's nature, it's method of propagation, it's characteristics, and so forth.
Predictions of it's effects would be required, and also (as is the case with all theories) the conditions that would falsify those predictions.
One of the common claims is that Chi can be projected outside of the body. That should be very easy to test with proper protocols.
Essentially, we'd be describing telekenisis. To date, no one has been able to display such ability under controlled conditions.
if we blasted them.
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