@fresco,
fresco wrote:
I did not say anything about "premises". I said to play "the syllogism game" you need to assume static set theory and objective properties which fix set membership. Berkeley's phenomenology rejects objective properties.
The syllogism, like all arguments require premises and a conclusion. The syllogism is defined as an argument which has exactly two premises. Berkeley
argues that since there is no good distinction that can be made between primary properties (objective properties) and secondary properties (subjective properties) all properties are secondary properties. That argument, formalized is:
1. If no distinction can be made between primary properties and secondary properties, then all properties are secondary properties.
2. No distinction can be made between primary and secondary properties.
3. Therefore, all properties are secondary properties.
That argument is a syllogism since it has exactly two premises.
Actually, that argument is unsound. It is unsound because the first premise is clearly false. And the second premise is also false. The first premise is false because it is obvious that just because no distinction can be made between two things, it does not follow that there is no distinction between them, nor does it follow that even if there is no distinction between them, that one of them must be the other, but the other cannot be the first. The second premise is also false since we can distinguish between primary and secondary properties.
But the argument is, indeed valid, since if the premises were true, then the conclusion would be true.
So there is no reason to think that Berkeley was not using ordinary logic to try to prove that there were no primary properties. Only, of course, his argument was unsound since both his premises were false.