Olivier Darrigol studied physics at the École Normale Supérieure in Paris, the history and philosophy of physics at the Sorbonne and at UC-Berkeley's Office for History of Science and Technology (OHST). He is the author of several books on the history of quantum physics, electrodynamics, hydrodynamics, and optics. He is currently a member of the SPHere research team at CNRS/Paris 7, and a Research Associate at UC-Berkeley's OHST.

The idea that we can establish foundational principles of physical theories on pure reason alone did not die with Newtons rejection of Cartesian rationalism. Darrigol, the author of a number of valuable works on the history of physics, explores latter day rationalisms, focusing on those that follow Helmholtz in seeking for necessary conditions on the interpretation and application of theories. Darrigol offers his own account on how theories must be interpreted and applied and how the necessity for these may very well be taken as establishing a limited kind of rational support for some principles of foundational physics.

• 1. Rationalism in the history of mechanics ; 2. The necessity of classical mechanics ; 3. From mechanical reduction to general principles ; 4. Geometry ; 5. Spacetime ; 6. Numbers and math ; 7. Classical field theories ; 8. Quantum mechanics ; 9. Necessity, theories, and modules

Olivier Darrigol studied physics at the École Normale Supérieure in Paris, the history and philosophy of physics at the Sorbonne and at UC-Berkeley's Office for History of Science and Technology (OHST). He is the author of several books on the history of quantum physics, electrodynamics, hydrodynamics, and optics. He is currently a member of the SPHere research team at CNRS/Paris 7, and a Research Associate at UC-Berkeley's OHST.

The idea that we can establish foundational principles of physical theories on pure reason alone did not die with Newtons rejection of Cartesian rationalism. Darrigol, the author of a number of valuable works on the history of physics, explores latter day rationalisms, focusing on those that follow Helmholtz in seeking for necessary conditions on the interpretation and application of theories. Darrigol offers his own account on how theories must be interpreted and applied and how the necessity for these may very well be taken as establishing a limited kind of rational support for some principles of foundational physics.

• 1. Rationalism in the history of mechanics ; 2. The necessity of classical mechanics ; 3. From mechanical reduction to general principles ; 4. Geometry ; 5. Spacetime ; 6. Numbers and math ; 7. Classical field theories ; 8. Quantum mechanics ; 9. Necessity, theories, and modules