You can't gather evidence against a metaphysical assumption. Metaphysical assumptions are interpretations of physical phenomena, and unfalsifiable as such.
A standard refutation of Berkeley goes thusly however.
Some of Berkeley's key assumptions.
1. To be is to be perceived.
2. The world is made of of perceivers and their perceptions.
3. The perceiver is unperceivable.
4. There is no external world, only minds.
A contradiction may be derived from these three assumptions which is devastating to Berkeley's position. If there is no external world, and to be is to be perceived how do perceivers come into existence. You can't say that perceivers being is not contingent on being perceived, because Berkeley's entire position is that to be is to be perceived. And if perceivers could be without being perceived, then why couldn't other things. But perceivers surely cannot be perceived, so then perceivers must not exist. However, we know that there exists at least one perceiver (you). So then being is not contingent upon being perceived.
"The perceiver is unperceivable."
Actually Berkeley suggested that we are all perceivers that are capable of being perceived as well.
He believed in God, which he suggested would serve as the ultimate perceiver, so even if no human mind is perceiving a thing, that thing would still exist as it is being perceived by God. His answer to your question of how could a perceiver come into existence would be God.
Being would remain contingent on being perceived by God.
---------- Post added 05-12-2010 at 02:41 PM ----------
That seems a little dogmatic, don't you think? And why are interpretations of physical phenomena unfalsifiable. Can't there be mistaken interpretations of physical phenomena?
In any case, if kicking the stone does not show Berkley's view is wrong, then nothing does.
Berkeley could easily argue away the kicking of the stone. The idea is that "physical" phenomena like a stone is simply an immaterial idea that we as perceivers are experiencing vividly. The stone does not exist physically, it exists as an idea, and your mind is interacting with the idea of a stone.
It would be like a character in a video game running into a wall. The wall is not physical, it was programmed to be perceivable by the character, and so the character perceives it as physical. The video game programmer would be God in Berkeley's view.
I actually thought you were being sarcastic when you posted that refutation originally, so that's why I said what I said, not to be facetious.
---------- Post added 05-12-2010 at 02:45 PM ----------
There are several things wrong with what Berkeley states, some of which are revealed by reading Hume. (Berkeley, by the way, was great at revealing problems with some of his predecessors' views.)
Frankly, I think if Berkeley had followed his program more consistently, he would have ended up a solipsist and an atheist, as one does not directly experience other people or god more than one experiences matter. And then he should have also thrown out the self as well, as all he really experiences is, as Hume famously put it, "a bundle or collection of different perceptions
". What some people imagine to be the self, or the "container" of these perceptions, is not experienced.
But, of course, it is another question whether or not he should have gone down the path that he did in the first place. For that, I will simply suggest reading articles about Berkeley and see what kinds of criticisms you can find. I will give you a hint: Most philosophers since Berkeley have been decidedly unconvinced by him.
"Frankly, I think if Berkeley had followed his program more consistently, he would have ended up a solipsist and an atheist, as one does not directly experience other people or god more than one experiences matter"
I don't think Berkeley would have led himself to Solipsism or Atheism.
Two of his primary assumptions that allowed him to suggest this philosophy in the first place were A) God Exists, and B) Many human minds exist with different perspectives.
Without God his entire philosophy breaks down into non sense.
---------- Post added 05-12-2010 at 02:51 PM ----------
I think it's a practical view, that is justified by its usefulness. Still, I wonder how he can speak so freely about a reality that can only be known via representation? He creates a dualism that he can only know one side of. And yet it makes perfect sense that he would do so.
I feel that Kant did the same sort of thing, and was criticized for the same reason. If reality-in-itself is unknowable, in what way does it exist? Except as a hypothetical cause of representation that must exist within this same zone of "representation"?
I'm not sure I understand the dualism you mentioned. I thought that Berkeley was a monist, in that all is immaterial, as either an idea or a perceiver of ideas. Essentially his philosophy is that we are all independent entities created by God living in a matrix programmed with God's ideas.
But everything, in his view, is made of whatever material God is made of. There is no second thing...
Unless you have some insight that I'm missing.