affirm vs assert

affirm and assert both are verbs.

Word	Noun	Adjective	Verb	Adverb
affirm	No	No	Yes	No
assert	No	No	Yes	No

As verbs, affirm and assert are synonyms defined as:

Other synonyms of affirm include aver, avow, swan, swear, verify.

affirm (verb)	assert (verb)
establish or strengthen as with new evidence or facts	postulate positively and assertively
to declare or affirm solemnly and formally as true	to declare or affirm solemnly and formally as true
say yes to	state categorically
	insist on having one's opinions and rights recognized