sobriety vs serious-mindedness

sobriety and serious-mindedness both are nouns.

Word	Noun	Adjective	Verb	Adverb
sobriety	Yes	No	No	No
serious-mindedness	Yes	No	No	No

As nouns, serious-mindedness is a hypernym of sobriety; that is, serious-mindedness is a word with a broader meaning than sobriety:

Other hypernyms of sobriety include earnestness, seriousness, sincerity.

sobriety (noun)	serious-mindedness (noun)
abstaining from excess	the trait of being serious
a manner that is serious and solemn
moderation in or abstinence from alcohol or other drugs
the state of being sober and not intoxicated by alcohol