@simon phil,
Nice discussion.
Its rather amazing how the notion that we're purely "reactive" strikes such a chord of discontent. I believe I see (and accept as correct) this notion since, but its definition, I cannot do anything which does not involve any other factors or elements (which would then put it in the realm of reactionism).
Hehe, almost feels like a self-professed/self-defined truth (an assertion whose constituent elements constrain/lead to only one conclusion, and is therefore of spurious value since it decides itself). Nonetheless...
I wouldn't equate acceptance of this notion to "everything's set in stone". Although I may react next Tuesday morning to an event, that event hasn't occurred (nor has many of its dependent factors, not yet). Cause and effect isn't linear; it is a tree with innumerable branches and tributaries that cross, collide and influence - most not visible to me. Or - perhaps a better way of putting it might be: I am on this path, I will hit a point 2 miles up where I'll make a reaction to a set of circumstances. Those circumstances are not yet staged. Thus, my reaction to that point can't really be said to be 'set in stone' - at least not yet. At that point? Sure... I could buy that, but there's an element of chaos/randomness we're not taking into account here (nope, not going there! :p )
... I think I just felt something in my head go *pop*. Time for asprin