Conclusion

Quantum theory does not describe the world and so contributes little to natural philosophy: it implies neither that a particle can be in two places at once, that a cat can be neither dead nor alive, that there is instantaneous action at a distance, nor that our observations create the world they reveal. Quantum entanglement does not say that the world is radically holist or non-separable, that the world is indeterministic or deterministic, that mind influences matter, or that consciousness plays a special role in the natural world. But the theory does have lessons to teach about how philosophy should approach topics including causation, probability, laws, composition, and ontology that traditionally fall within metaphysics. Here the quantum revolution reinforces the pragmatist lesson that such topics are best approached by asking why agents like us should have developed the concepts we have when physically situated in a world like this.