Abstract

There is a common (although not universal) claim among historians and philosophers that Copernican theory predicted the phases of Venus. This claim ignores a prominant feature of the writings of, among others, Copernicus, Galileo and Kepler-the possibility that Venus might be self illuminating or translucent. I propose that such over-simplifications of the history of science emerges from "psychological predictivism", the tendency to infer from "E is good evidence for H" to "H predicts E." If this explanation is correct, then in cases where evidence is less blatant the history of science (and philosophies of science that rely on it) has probably been seriously distorted in a predictivist direction.