If you choose to define an action as representing free will only if it is uncaused then first, you've made up a definition entirely at odds with the normal English usages and, second, your definition is useless because it only cuts actions into those actions that exist and those that don't and we already have a perfectly good word for that so the new one is redundant.
> If you choose to define an action as representing free will only if it is uncaused then first, you've made up a definition entirely at odds with the normal English usages
I was trying to be precise, and assumed you agree that something that's part of a causal chain cannot be reasonably be called "free" by any common sense definition. You can't change the past after all, can you? If not then you're a product of circumstance just like everything else in the universe.
Now, if you told a normal person that someone in that circumstance couldn't have done anything except buy the soda they would agree that would mean I didn't have free will but they wouldn't see why. To them the "My decisionness" and "Could have been differentness" are the same thing. But philosophically we have to choose one or the other and it's both more useful, in terms of carving reality at the joints, and in greater accordance with common usage to pick "My decisionness" as what we interpret "free will" to mean.
I'm sorry I'm not directly addressing your point about changing the past, but that's because I'm still rather confused by how it relates to free will. Certainly I'd say that nobody can change the past.
Yes you can call it free since you have defined free to mean acting according to your motivations, just like I predicted in my original comment. But since your behavior is caused by your motivations, and your motivations have it's own causes, and so on, I really don't see what you actually win (except the language game) by describing the process as free. It's about as free as the last cogwheel in a machine.
> I'm sorry I'm not directly addressing your point about changing the past, but that's because I'm still rather confused by how it relates to free will.
Suppose your will is a function of your brain, and suppose that your brain is a function of gene expression and environmental stimuli. Suppose you are unable to choose your genes, and suppose that you are unable to alter the history of environmental stimuli. It follows that the causes of your will are outside your control. If you don't control your will, then your will is not free.