Here's my list of examples again, this time with appropriate comments.
1 - Is it possible to test if someone can run faster than 40 km/h?
Maatorc says this is possible: "use a stopwatch". We'd also need something to measure distance, and check that the person is really running without any hidden technical help (some cleverly designed machinery in the shoes, for instance). Once we'd got the conditions sorted out, we could then see if the person runs faster than 40km/h. This does not test how the person runs faster than 40km/h, only that they're doing it using their own physical and mental powers.
2 - Is it possible to test if someone can levitate above the ground for at least one minute?
Maatorc says this is impossible. There is however no basic difference between this example and the previous one. We'd need a watch, and some means to check that the person isn't using any technical help (hidden wires or levers, very strong magnets...). Then we could see if the person could levitate for more than a minute. This wouldn't tell us how the person is levitating, only that they are doing it using their own physical and mental powers.
3 - Is it possible to test if someone can tell what sort of object is hidden in a sealed opaque contained by shaking the container?
Maatorc says no. Why not? The test is simple: give the person the container, let them shake it, let them say what they think is concealed within, then open the container to check if they are right or wrong. In fact most people can indeed work out something about the object just by shaking the container. If the choice of objects were suitably limited - let's say either a small block of wood, a bottle of wine, a rubber ball, an inflated balloon or a bell - I could easily say which object was hidden in the container, without needing any paranormal help.
4 - Is it possible to test if someone can tell what sort of object is hidden in a sealed opaque container by mental powers, without touching the container?
Maatorc says no. Why not? This test is also simple: show the person the container, don't let them touch it, let them say what they think is concealed within, then open the container to check if they are right or wrong.
5 - Is it possible to test if someone can find metal using a metal detector?
Maatorc says yes. I agree: give the person a metal detector, devise a test where (for instance) there is some metal in just one of ten containers, see if they can find the metal using the detector.
6 - Is it possible to test if someone can find water using a dowsing rod?
Maatorc says no. Why not? Give the person a dowsing rod, devise a test where (for instance) there is some water in just one of ten containers, see if they can find the water using the dowsing rod.
7 - Is it possible to test if someone can move an object by breathing on it?
Maatorc doesn't bother to comment on this one. Apparently he thinks it's possible, since he removed it from my list when he quoted it. It seems simple enough: put the object in front of the person, let them blow on it, see if it moves. Of course you need to check if the person is not using any other method to move the object, such as invisible thread or hidden magnets.
8 - Is it possible to test if someone can move an object by mental power?
Maatorc says no, it's not possible. This is strange, because this test is as simple as the previous one: put the object in front of the person, see if they can make it move without touching it. Of course you need to check if the person is not blowing, using invisible thread or using hidden magnets.
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All these cases are similar: they are testing for the existence of something, not examining its inner workings. If, for example, someone is measured running at more than 40km/h, scientists could examine the person and try to work out how they run so fast. If someone is shown to levitate, scientists would certainly be interested in looking into how this happens.
Of the 8 tests above, tests 2, 4, 6 and 8 would be suitable for the MDC.