Can a 700‑Year‑Old Razor Eliminate 90% of Unnecessary Assumptions?

Ockham’s Razor

When two explanations have comparable explanatory power, the one that requires fewer assumptions should be chosen. The principle removes unnecessary assumptions rather than advocating simplicity for its own sake.

Historical illustration

The geocentric model explained planetary motion by adding dozens of epicycles; each observational discrepancy required an additional circle, inflating the number of assumptions. In 1609 Kepler introduced three laws of elliptical orbits, explaining the same phenomena with only three assumptions. Ockham’s Razor selects the model with fewer assumptions.

Three‑step practical framework

List all assumptions – Write down every implicit, default, or taken‑for‑granted assumption related to the decision.

Question each assumption’s necessity – Ask whether the conclusion still holds if the assumption is removed; if it does, the assumption is redundant.

Retain only indispensable core assumptions – Keep only those assumptions that, when removed, cause the conclusion to fail; distinguish factual necessities from those driven by fear.

Everyday applications

When an appliance fails, first check the power cable (the simplest assumption) before assuming a complex motherboard fault. In medicine, the adage “when you hear hooves, think horse, not zebra” reflects the same principle.

Philosophical note

Einstein is quoted: “The highest goal of theory is to make the irreducible elements as simple as possible without losing the essence.” The razor cuts away unnecessary assumptions; genuine complexity should be respected, not avoided.