"All known theories of physics - from classical mechanics all the way to general relativity quantum field theory - can be written in this way: a collection of objects and a recipe to build a Lagrangian from those objects, with the movement of those objects determined by a path that minimizes the Lagrangian."<p>I think Quantum Mechanics doesn't reduce to this, it's a probabilistic theory.<p>A similar take from Peter Woit:<p><a href="https://www.math.columbia.edu/~woit/laguardia.pdf" rel="nofollow">https://www.math.columbia.edu/~woit/laguardia.pdf</a>