therefore vs thence

therefore and thence both are adverbs.

Word	Noun	Adjective	Verb	Adverb
therefore	No	No	No	Yes
thence	No	No	No	Yes

As adverbs, therefore and thence are synonyms defined as:

therefore and thence: (used to introduce a logical conclusion) from that fact or reason or as a result

Other synonyms of therefore include hence, so, thus.

therefore (adverb)	thence (adverb)
(used to introduce a logical conclusion) from that fact or reason or as a result	(used to introduce a logical conclusion) from that fact or reason or as a result
as a consequence	from that place or from there
	from that circumstance or source