I'm reading Ivar Ekeland's The Best of All Possible Worlds, and I can't resist posting this quotation:
We are a far cry from Plato, for instance, who taught that the objects we observe are but images, or shadows, of originals, the only true and real Objects, which exist in a world above one own, the world of Ideas. [...] Poincaré points out that science does not need that kind of belief: there is no need for objects to exist in any other way than to relate our sensations with common experience. Clearly there is no more room for metaphysics: science can be concerned with relating only facts, not things.
A residual Platonism often confuses natural science, mathematics, and computer science. Time to read Poincaré.