Here's why:
* They are not proper nouns: These words are common nouns, referring to general concepts rather than specific individuals or places. Proper nouns (like names, cities, and countries) are capitalized.
* They are not titles: When used in casual conversation or general writing, these words are not considered titles, which would typically require capitalization.
However, there are some instances where these terms might be capitalized:
* As part of a course title: If you're referring to a specific course, like "History 101" or "Math 205," the capitalization would be appropriate.
* In a formal context: In very formal writing, like academic papers or legal documents, these terms might be capitalized for emphasis.
Generally, you can use lowercase for these terms unless there's a specific reason to capitalize them.