As a student, you’ve likely encountered the concept of “common knowledge” before, particularly when it comes to citing sources in your academic writing. But what exactly constitutes common knowledge, and when must you provide a citation?
Examples of Common Knowledge
Examples of common knowledge are:
- Information that appears across many sources without a clear origin, such as famous historical dates
- Long-established facts or theories that are foundational to a field, like fundamental equations in physics
It does not include:
- Data and statistics gathered in empirical studies. These should always be cited.
- Interpretations or arguments. If a statement could be reasonably disputed, provide a citation.
The examples below show how subtle the distinction can be:
Statements about APA Style citation
“APA is a common citation style used by students.” This is an undisputed and easily verified fact. It is common knowledge.
“APA Style is mainly used in the social sciences, business, and nursing.” For a reader familiar with research, this is likely to be accepted as common knowledge. For a more general readership, you might need to cite it.
“APA Style is used in more than 90,000 papers per year.” This is not an undisputed fact and should be attributed to one or more sources.
Statements about the Amazon rainforest
“The Amazon is the world’s largest tropical rainforest.” This is a widely known fact you can assume any reader will accept. It is common knowledge.
“Due to deforestation, the Amazon has been rapidly decreasing in size since the 1960s.” If you are writing an in-depth paper on Amazon for an expert reader, this would likely be accepted as common knowledge. If you are writing a basic or introductory paper for a more general audience, you should provide a citation.
“The cattle sector is responsible for 80% of deforestation in the Amazon.” This statistic is derived from specific research. It should be cited even if it is widely accepted to be true. You should always give the source of any figures or statistics.
The examples demonstrate that the boundary between common knowledge and information requiring citation can be subtle. Writers should carefully consider their target audience and err on the side of providing citations to support any claims that are not widely accepted facts.
Do I Need a Citation?
When writing academic papers, content considered common knowledge does not require a citation. Common knowledge encompasses information that is widely accepted, undisputed, and easily verifiable without being attributable to a specific source.
While it may be tempting to include a citation for every statement to avoid potential plagiarism issues, over-citing can actually weaken the academic quality of your writing. The key is to discern when a piece of information qualifies as common knowledge versus requiring a cited source.
To make this determination, consider the following questions:
Who is my target audience, and what background knowledge can I assume they possess?
If you are writing for a general readership, you may need to provide more context and citations than if you are addressing subject matter experts within your field.
Is this a statement my reader could reasonably dispute or contest?
If the information is a foundational, widely accepted fact within your discipline, it is likely common knowledge. However, if the statement could elicit skepticism or require additional evidence, a citation is warranted.
Can this information be easily verified across multiple credible sources?
If a quick online search returns consistent, corroborating facts from reputable scholarly sources, the content can be treated as common knowledge. Contradictory or hard-to-find sources suggest the need for a citation.
Navigating the boundaries of common knowledge requires careful consideration of your specific writing context and audience. When in doubt, it is generally better to err on the side of providing citations to support your statements and avoid any potential plagiarism issues.