First principles thinking is a problem-solving approach that involves breaking down complex problems or systems into their individual, fundamental building blocks and using that understanding to develop new and innovative solutions. The idea is to start from a foundational understanding of the underlying principles and concepts that govern a particular system or issue, rather than relying on preconceived notions, heuristics, or analogies.
For example, in physics, first principles thinking involves reducing a physical phenomenon to its most basic laws and principles, such as the laws of motion and the laws of thermodynamics. In business, first principles thinking might involve breaking down a company's operations into its core components and understanding how they work together to achieve a particular outcome.
Adopting a first principles thinking approach can lead to more innovative and effective solutions, as it forces one to deeply understand the problem and consider all possible options, rather than simply relying on established approaches or copying what has worked in the past. While first principles thinking has been around for ages, it has become culturally relevant and talked about due to Elon Musk siting it as his main mental model and reason for his success.