You may have heard people say that you do not have to cite your source when the information you include is “common knowledge.” But what is common knowledge?
Broadly speaking, common knowledge refers to information that the average, educated reader would accept as reliable without having to look it up. This includes:
- Information that most people know, such as that water freezes at 32 degrees Fahrenheit or that Barack Obama was the first American of mixed race to be elected president.
- Information shared by a cultural or national group, such as the names of famous heroes or events in the nation’s history that are remembered and celebrated.
- Knowledge shared by members of a certain field, such as the fact that the necessary condition for diffraction of radiation of wavelength from a crystalline solid is given by Bragg’s law.
- However, what may be common knowledge in one culture, nation, academic discipline or peer group may not be common knowledge in another.