You're not playing. You're evading, running away.
Joints don't move anything.
The anatomy of the finger is not what caused the finger to move, in a manner you decide to move it and at a time you decide to move it.
Sure; But then, YOU don't decide to move your fingers either.
If another1 was gullible enough to go along with your absurd experiment, then what caused his finger to move wasn't his 'mind', any more than it was his muscles. The muscles only act because the brain sends the appropriate signals to them; And the brain only acts because YOUR POST sent the appropriate signal to it.
I am prepared to believe that you are UNAWARE that your decisions are the response to the totality of the inputs of your senses, as processed by the brain; But I cannot accept your apparent belief that you are able to make decisions without reference to those inputs.
There is no 'first mover' in your brain that drives what it decides; Just inputs and memories.
I understand that you find this fact unpalatable; But it remains a fact whether you like it or not. Brains respond (often in very complex ways) to their inputs and memories - and there is nothing else. it FEELS as though there is something else, but when we use the scientific method, in place ouf our feelings, we see that there cannot be anything else.
Of course, you are welcome to argue that your feelings are a better guide to reality than the scientific method is; But then everyone will, quite rightly, laugh at you.