Problem
Consider the problem of driving. You could define the actions in terms of the accelerator, steering wheel, and brake, i.e., where your body meets the machine. Or you could define them farther out, say where the rubber meets the road, considering your actions to be tire torques. Or, you could define them farther in, say where your brain meets your body, the actions being muscle twitches to control your limbs. Or you could go to a really high level and say that your actions are your choices of where to drive. What is the right level, the right place to draw the line between agent and environment? On what basis is one location of the line to be preferred over another? Is there any fundamental reason for preferring one location over another, or is it just a free choice?