explores the historical and philosophical shifts that enabled the Enlightenment and the birth of modern science. It argues that while rejecting authority and embracing testability were important steps, the truly decisive factor for progress was the search for hard-to-vary explanations. Traditional myths and "rules of thumb" are identified as bad explanations because their details can be easily changed to fit any observation, making them effectively meaningless. In contrast, scientific advancement relies on a tradition of criticism that seeks to describe the underlying reality behind appearances. Ultimately, the source suggests that science is defined not just by experiment, but by the pursuit of theories that cannot be easily altered without losing their explanatory power.