Nancy Cartwright ( 24 Jan1944- ) is a principle defender of the view that the practice of science does not support the thesis of the unity of science, urged by Carnap and other logical positivists, nor yet post-logical empiricist realism, particularly construed as realism about fundamental laws. She advocates instead the picture of science as composed of a patchwork of domains each with its own methodological and theoretical commitments, and realism directed not at laws or supposedly universal equations, but at capacities, dispositions, and causes as manifested in local experimental contexts and local theoretical investigations. Supposed paradoxes such as the measurement problem of quantum mechanics are illustrative of a methodological mistake, in elevating equations valid in one local patchwork of phenomena to another, and a reflection of the quest for a monolithic metaphysics at odds with actual experimental practices.
Cartwright graduated in mathematics at the University of Pittsburgh in 1966; her PhD was written under Brian Skyrms at the University of Illinois at Chicago. She has held positions at the University of Maryland, Stanford University, and the LSE. She is currently Professor of Philosophy at the University of Califorinia at San Diego, and at Durham University.