How are arguments different from physical actions (for example what is the difference between telling someone something and applying electric shocks to them) in a world without free will?
Aren’t they all purely physical stimuli that produce a certain response?
I am sure an electric shock also produces a certain state of mind.
Well, physical actions come in many different flavors. One of those flavors is beliefs, i.e. a particular neural configuration with a certain semantic relationship within its host and the outside world. E.g. one that disposes further relevant neural configurations and relevant behaviors. I don't see the problem.
The same as it's always been. You've just been redpilled. Just as usual, as it's always been since you were alive; its the way your brain is shaped and connected.