The question is of reflexes.
When the doctor taps your knee and you involuntarily kick, it is a reflex. When a bright light is shown in your face and your pupils contract, it is a reflex. When you touch a hot surface and pull your hand away, it is a reflex.
A reflex is causal. Something happens and an involuntary response is the result. It happens outside of our conscious control.
IF you touch a hot surface THEN you pull your hand away.
You touch a hot surface.
—————————————
You pull your hand away.
Is this the case?
If it were this simple, it would be fair to write it like like this:
IF you touch a hot surface THEN your hand pulls away.
You touch a hot surface.
—————————————
Your hand pulls away.
However, we can train our reflexes. The heat that would cause me to pull away from a hot stove might not even make a chef flinch. Everyone has held back a sneeze, to varying success. Experience, training and conditioning can modify our responses. Hence some part is involuntary, some is not, making reflexes a special, fundamental phenomenon.
So here is the rub: when I have such a reflex I have a unique experience of something outside my control, if only in part, that is also connected to me. When I sneeze, I cannot deny this.
I Sneeze, Therefore I Am — Sternuō Ergo Sum
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