Temporal naturalism
arXiv Preprint Archive October 31, 2013 Lee Smolin
Two people may both call themselves naturalists yet hold fundamentally different views about time, laws of nature, and the role of mathematics in physics. These differences rarely affect ordinary science, which studies small subsystems against a fixed background, but become critical when considering the entire universe, where no such background exists. The key divide is the conception of time: temporal naturalism holds that the succession of present moments is real and that laws of nature evolve, while timeless naturalism treats laws as immutable and the present moment as an illusion.