Razor be used on both sides, with two open edges. The blade on the double-edged safety razor is slightly curved to allow for a smoother and cleaner shave. In 1901, the American inventor King Camp Gillette, with the assistance of William Nickerson, patented a new variation of safety razor with disposable blades. Gillette realized that a profit could be made by selling an inexpensive razor with disposable blades. This has been called the razor and blades business model, and has become a very common practice for a wide variety of products. Many other brands of safety razors have come and gone.
Hitchens's razor by Hitchens published in 2007. Hitchens's razor is actually an English translation of the Latin proverb "" ("What is freely asserted is freely dismissed"), which was commonly used in the 19th century. It takes a stronger stance than the Sagan standard ("Extraordinary claims require extraordinary evidence"), instead applying to even non-extraordinary claims. Hitchens's razor Hitchens's razor is an epistemological razor asserting that the burden of proof regarding the truthfulness of a claim lies with the one who makes the claim, and if this burden is not met, the claim is unfounded, and its opponents need not argue further in order