Occam's Razor is a principle of thought that suggests how we should always prefer simple explanations to complex ones. It got its name by William of Ockham, who was a Scholastic philosopher in the 14th century. This principle is also known as the law of economy/parsimony, where simplicity is a favorable solution. A more complex theorem of the law says that "plurality should not be posited without necessity," meaning that we should not strive to make many solutions when we face a problem, but should pick just one.
Simplicity Equals Perfection
Although this way of thinking is associated with William of Ockham, the concept actually originated in France. A theologist and philosopher, Durandus of Saint-Pourçain, explained that abstract way of thinking is just apprehension of a real entity, and therefore unnecessary. Similar approaches were used in the law of the economy of Nicole d'Oresme and Galileo's hypothesis of the heavens.
Occam's Razor, on a first look, is something that should be a perfect choice for any scientific method. If simplicity equals perfection, then everyone should indulge in using the principle to prevent from overthinking and overcomplicating the solution. However, this law is not a law per se. It does not prove anything, and it merely serves as a tool that can suggest how the more straightforward solution is commonly the correct one.
Einstein Vs. Lorentz
A famous example of the use of Occam's Razor comes from the field of physics. Both Einstein and Lorentz were concerned with what happens when we approach closer to moving with the speed of light. They have both concluded that we actually slow down as we approach that type of speed. However, Lorentz used the concept of "ether" as a place where this happens.
This conclusion is based on something that does not exist in the science world, the "ether." That element of the equation was problematic. Einstein's theory did not have problems with the validity of the terms that were used. It can, therefore, be considered as accurate.
Problems With Occam's Razor
We can encounter two problems if we use Occam's Razor as a method to judge the validity of an explanation. First of all, to say that something is or is not simple is a very subjective field to tackle. Establishing ground rules which determine what simple actually is, proves to be much harder than it seems. Secondly, it is challenging to collect empirical evidence that will demonstrate how simplicity can be the same as truth. This idea, which dates back to Aristotle, how perfection is the foundation of simplicity, is not something that actually works in science in general.
Occam's Razor can best serve as a temporary stop where we can start to think about what the possible solution is, and not a place where we should make our final conclusions. In science, nothing trumps the importance of empirical evidence, and quick decisions are usually not the way to go.