I'm saying that *if* we have free will, then all other beings have free will. (I believe that we have free will but I don't know.)
There may be a gradient but THERE IS NO LINE. Anywhere you drew the line would be arbitrary, based on one's own biases.
It wouldn't be based on my own biases, but evidence that a being either exhibits whatever you wish to associate with free will or does not. How is that arbitrary? There must be some reason that some beings are capable of realizing free will while others are not, if that is even the case, no?
On what basis do you think that we humans are so special anyway?
We have special insight in only one being on the planet and that is us. We know that we make conscious choices. That is not to say that we have free will, necessarily, though. I guess it all depends on your definition of free will. Still, even if we were an unbiased observer (impossible, I know, but bare with me), we would still likely come to the conclusion that humans exhibit behavior that other organisms do not that seem, at least at a glance, to not be based on forms of instinctual behavior found in "lesser" beings. Then there is the Bible.
Actually, having watched paramecia a fair amount, they swim one way or the other. They go forwards or backwards. They stay in one place (more or less) or they move. They ingest something that they encounter or they don't. Those are all ACTIONS.
Are they really making choices? I don't know. But then again, I'm not sure that we really are either. All I know is that THERE IS NO LINE.
Reacting based on instinct has nothing to do with a free will. I don't know why you would draw the conclusion the because a being is capable of making an action that said action is necessarily a free choice (insofar as is also the case with us, at least).
If you do not even know if we have free will, I would really like to know how you can be so certain that there is no line. Many believe that freedom of the will comes at a certain stage of intelligence (similar to theories of consciousness). What good evidence do you have to refute these theories?