This essay is dominated by three themes that recur contrapuntally in Heisenberg’s writings: observation, description, and ontology—prompted always by a concern about the role played by the subjective inquirer in scientific meaning-making, and by the ontology of scientific claims. Among the related themes are; the tension between paradigmatic concerns with structure and philosophical concerns with reality, the possibility of scientific revolutions, such as relativity and quantum mechanics, that can overthrow the classical traditions of natural science and the inadequacy of a (...) psychophysical parallelism for an epistemology of reason. The influence of Husserl and Heidegger is in his neokantian concern about the role of subjectivity. Heisenberg was a long-time friend of Heidegger and familiar with Heidegger’s hermeneutical phenomenology and its critique of Greek philosophy; he also contributed an essay to a Festschrift in Heidegger’s honor in 1959. (shrink)