The core idea of Occam’s razor can be expressed in eight Chinese characters: do not multiply entities unnecessarily.
It means that for a thing, if there is no need for it to exist, do not actively add it or passively let it appear. Conversely, if it does appear, it should be removed the way a razor shaves off excess hair.
If several solutions can solve the problem, choose the simplest one; if several paths can reach the goal, choose the shortest. In the scientific realm, if several theories lead to the same conclusion, choose the more concise one. In general, choose whichever is simpler. Make complex things simple while retaining what is necessary. Because complexity causes people to lose their way.
The insight behind this is important. “Entities should not be multiplied without necessity”—why not say, “If unnecessary, shave it off”? Because the key to razor thinking is that I have it, but ideally do not need it. When you allow an unnecessary entity to appear, it will begin to prove that its existence is necessary. Think about the things in life that you want when you do not have them, but that turn out to be of little use after you buy them—and that you feel guilty about not using, such as snacks, clothes, and soy milk makers. Besides the unnecessary entity itself feeling the need to prove that its existence is necessary, other entities that were originally necessary can also, because of its presence, spontaneously establish new forms of collaboration or new habits related to it. A soy milk maker may even lead you to buy more beans than you can finish.
By this point, using the razor again becomes difficult: shaving it off will hurt and cause injury. You then need to weigh the options, leading to hesitation. “Do not multiply entities without necessity” rather than “shave entities off” tells us that the best strategy of razor thinking is to prevent problems before they arise. The true meaning of the blade is not to kill, but to remain sheathed; the true meaning of the razor is not to shave, but to distinguish the complex and preserve the simple, keeping a blade in your heart and retaining only what is necessary. Having a blade in your heart without needing to use it is the best state.