In phrases such as “the discipline of geography,” geography should not be capitalized.

Should geography have a capital letter?

Note, however, that names of disciplines and school subjects are not capitalized unless they happen to be the names of languages: I'm doing A-levels in history, geography and English. Newton made important contributions to physics and mathematics.

Do you capitalize the name of a field of study?

Don't capitalize names of school or college studies, fields of study, majors, minors, curricula or options unless they contain proper nouns when no specific course is referenced. He is studying geology. She is majoring in engineering. The Department of English offers a specialization in creative writing.