Complex sentence: Chisholm was a metaphysical Platonist in the tradition of Bertrand Russell, and a rationalist in the tradition of Russell, G. E. Moore, and Franz Brentano; he objected to Quine's anti-realism, behaviorism, and relativism.
Split into simpler sentences: Chisholm was a metaphysical Platonist in the tradition of Bertrand Russell. And a rationalist in the tradition of Russell, G. E. Moore, and Franz Brentano; he objected to Quine's anti-realism, behaviorism, and relativism.