There's a saying in linguistics that "a language is a dialect with an army and a navy" [0]. Linguists recognize that where you draw boundaries between languages is essentially arbitrary, even more so than boundaries between biological species. It tends to be that a language is a language if and only if some sovereign state declares it to be so, otherwise it's a dialect.
This is also how you get Portuguese as a distinct language from Spanish even though the two are more mutually intelligible than Scots (a "dialect") and American English are. Portugal has the sovereign government to back up its claim to having its own language where Scotland does not.
This is also how you get Portuguese as a distinct language from Spanish even though the two are more mutually intelligible than Scots (a "dialect") and American English are. Portugal has the sovereign government to back up its claim to having its own language where Scotland does not.
[0] https://en.wikipedia.org/wiki/A_language_is_a_dialect_with_a...