Fact Check: Are PM and AM capitalized?

Are PM and AM Capitalized?

The claim in question is whether the abbreviations "AM" and "PM" should be capitalized. This topic often arises in discussions about writing style, particularly in formal contexts, and can lead to confusion due to varying conventions across different style guides.

What We Know

1. Definitions: "AM" stands for "Ante Meridiem," meaning "before noon," while "PM" stands for "Post Meridiem," meaning "after noon" 2.

2. Capitalization Rules:

   • The Chicago Manual of Style states that "AM" and "PM" should be capitalized at all times 58.
   • Other sources, like The Editor's Manual, suggest that capitalization may depend on the style guide being followed, indicating that both "a.m." and "p.m." (in lowercase with periods) are also acceptable 39.
   • Grammarist notes that while the official spelling includes periods (A.M. and P.M.), lowercase forms (am and pm) are increasingly used in casual writing 7.

3. Usage Variations:

   • Some writers prefer to use lowercase forms (a.m. and p.m.) in less formal contexts 410.
   • The Western Michigan University style guide emphasizes that "AM" and "PM" should be avoided in favor of "a.m." and "p.m." for clarity and consistency 1.

4. General Consensus: There is no universally accepted rule; the choice often depends on the specific style guide being adhered to. For example, academic and professional writing may lean towards the capitalized forms, while casual writing may favor lowercase.

Analysis

The sources consulted provide a range of perspectives on the capitalization of "AM" and "PM," reflecting the lack of a single authoritative answer.

• Credibility of Sources:

  • The Chicago Manual of Style is widely regarded as a definitive guide in publishing and academic writing, lending high credibility to its recommendations 5.
  • The Editor's Manual is also a respected resource, though it may not have the same level of authority as the Chicago Manual 3.
  • Sources like Grammarist and Western Michigan University provide useful insights but may not be as universally recognized, which could affect their reliability 17.

• Potential Bias:

  • Style guides may have inherent biases based on their target audience (academic vs. casual writers), which can influence their recommendations. For instance, a guide aimed at formal writing may advocate for stricter adherence to capitalization rules.

• Methodological Concerns: The variations in capitalization rules suggest that the methodology behind these recommendations is largely based on tradition and the evolution of language rather than empirical evidence. This could lead to inconsistencies in usage across different contexts.

• Conflicts of Interest: Some sources, particularly those affiliated with educational institutions, may have a vested interest in promoting certain styles that align with their teaching methodologies.

What Additional Information Would Be Helpful?

To further clarify the issue, it would be beneficial to have:

• A comprehensive survey of various style guides used in different fields (e.g., journalism, academia, business) to see how they address the capitalization of "AM" and "PM."
• Insights from linguists or language experts on the evolution of these terms and their usage in contemporary writing.
• Examples of usage from a wide range of publications to observe trends in real-world applications.

Conclusion

Verdict: Partially True

The claim regarding the capitalization of "AM" and "PM" is partially true, as the evidence indicates that both capitalized ("AM" and "PM") and lowercase ("a.m." and "p.m.") forms are acceptable, depending on the style guide in use. The Chicago Manual of Style advocates for the capitalized forms, while other guides allow for lowercase usage, particularly in informal contexts. This variability highlights the lack of a universally accepted rule, suggesting that the choice often hinges on the specific writing context and audience.

However, it is important to note that the recommendations from different style guides may reflect biases based on their intended audience and the evolution of language rather than empirical evidence. Therefore, while there is a general consensus on the existence of both forms, the absence of a definitive answer introduces a degree of uncertainty.

Readers are encouraged to critically evaluate the information presented and consider the context in which they are writing, as well as the style guide they are following, to make informed decisions regarding capitalization.

Sources

1. Times | Writing Style Guide | Western Michigan University. Retrieved from https://wmich.edu/writing/rules/times
2. AM / PM - Common Errors in English Usage and More. Retrieved from https://brians.wsu.edu/2016/05/16/am-pm/
3. How to Use AM and PM - The Editor's Manual. Retrieved from https://editorsmanual.com/articles/time-using-am-pm/
4. AM or a.m., PM or p.m.: Do I Capitalize AM and PM? Retrieved from https://writingexplained.org/am-or-a-m-pm-or-p-m-do-i-capitalize-am-and-pm
5. FAQ Item - The Chicago Manual of Style Online. Retrieved from https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Abbreviations/faq0095.html
6. punctuation - AM/PM vs a.m./p.m. vs am/pm - English Language & Usage. Retrieved from https://english.stackexchange.com/questions/22784/am-pm-vs-a-m-p-m-vs-am-pm
7. A.M. or P.M. - How to Write Them (+ Examples) - GRAMMARIST. Retrieved from https://grammarist.com/usage/a-m-and-p-m/
8. When should you capitalize AM and PM? Retrieved from https://www.chicagomanualofstyle.org/qanda/data/faq/topics/Abbreviations/faq0103.html
9. Are AM and PM Capitalized? - The Editor's Manual. Retrieved from https://editorsmanual.com/articles/am-pm-capitalization/
10. AM and PM / a.m. and p.m., Things You Probably Overlooked. Retrieved from https://www.linkedin.com/pulse/am-pm-things-you-probably-overlooked-usage-tips-michael-peterson