Anne Curzan at Lingua Franca writes about a phenomenon I’ve noticed but not really thought about: the distinction between the traditional use of hence meaning ‘as a result, for this reason’ as an introduction to full clauses (her example: “Hence, vaccines with enhanced serotype coverage … might be needed to prevent IPD in this age group in the near future”) and its modern use to introduce a noun phrase (“Hence the value of strengthening skills now”). Curzan says:
It will probably come as no surprise to readers that hence is one of the conjunctive adverbs that strongly prefer academic prose over other registers. […] Hence is more comparable in frequency with nevertheless in academic writing (74.50 pmw).
The frequency of hence in spoken language, in comparison, is low. It puts hence in the range of words like validity and contemplate in the spoken section of this database. […]
Despite the formal feel of hence, it seems more colloquial when it introduces a noun phrase rather than a clause. […]
The frequency of hence overall seems to be declining in written American English (it is holding steadier in British English).
I agree that hence “seems more colloquial when it introduces a noun phrase rather than a clause,” and in fact if I use it that way I feel like I do when I use fun as an adjective (“a fun time”). But I’m happy if people use it at all, since it’s a useful little word (with a fun etymology: it’s the obsolete adverb hen plus the adverbial genitive suffix -(e)s, as in –wards). Do you use it, and if so do you use it to introduce a noun phrase or only a clause?