From PhilPapers forum Philosophy of Mind:

The 'Explanatory Gap'
Reply to Derek Allan
DA: "For the unlettered outsider like me, what is 'telekinetic dualism' exactly?"
"Telekinesis" (or "psychokinesis") is often also called "mind over matter": It's spoon-bending by Uri Geller. Not just "action at a distance" as in electromagnetism or gravity, but action at a distance caused by mental power alone. It's what psychics do. Spooky stuff.

I (and I assume you) don't believe a word of it.

But even when I bend a spoon with my hands, rather than at a distance, it feels as if it is my mind that is causing the bending, by causing my hands to bend the spoon.

The alternative is that it is electrochemical activities in the motor regions of my cerebral cortex that are causing my hands to bend the spoon, and that my mentally willing it had nothing to do with it -- except that it was quite closely correlated with it. 

(How closely correlated is still a matter for some debate, as, for example, the work of Benjamin Libet might possibly be showing: It could be that an unfelt cerebral event very slightly precedes my feeling of willing my hand to move.)

So telekinetic dualism would be true if there really existed a mental force, rather like the other 4 fundamental forces of nature -- electromagnetism, gravitation, strong subatomic; weak subatomic (if there are indeed 4, for they may be destined to be unified by some grand theory one day) -- and that 5th force, not the other 4, were the cause of the movement of my arm.

But there is no 5th force. The electrochemical/mechanical brain state preceding my movement, and triggering it, explains the cause of my movement as fully as its trivial counterpart does in a simple robot (except of course that the brain is much more complicated and capable); and whether the trigger point in the causal chain coincides with the moment I feel I am initiating the movement or precedes it slightly does not matter a whit: Unless telekinetic dualism is true, my feeling that I am doing it because I feel like like it in reality plays no causal role in my movement (even though the feeling is real enough).

And that is the mind/body problem. Telekinetic dualism would have been the solution -- if it had been true. But it isn't. There is no mental force, even though it feels like it: It's all matter over matter. But we cannot explain why or how, because there is no causal room. That's the explanatory gap.

-- SH