Transcript: One idea that does not fit neatly into theories of the scientific method is the idea of aesthetics. Science does have aesthetics in its theorizing. In the modern scientific method aesthetics usually apply to the mathematical description of nature. So when we talk about aesthetics in physics or astronomy we’re talking about principles of conservation, the conservation of charge, conservation of quantum number, conservation of energy, or of symmetry; the symmetry between matter and antimatter, between time flowing backward and time flowing forward. In the 1930s beta decay seemed to provide a violation of the cherished law of the conservation of energy. Pauli hypothesized an unseen, uncharged, undetected particle called the neutrino to preserve this symmetry principle. Thirty years later the neutrino was discovered. Heisenberg solved the equations of quantum mechanics and came up with two equal and opposite solutions. One corresponding to normal matter, the other to a form of matter with the opposite quantum properties, we call it antimatter. Four years later the positron was discovered. The idea of symmetry and aesthetics in science has a powerful place in our understanding of the natural world.