parts of speech - Is "University Challenge" right that this is a gerund?

The full context is below, but the basic question is: is the word spending in the following example really a gerund, as claimed by the University Challenge question-setters? My "best guess" would be that it is an example of a present participle or the progressive aspect.

Q: Give the single word gerund that completes the opening statement of Francis Bacon's essay 'Of Expense': 'Riches are for spending'.

Source: "Open University" Question, pre-2010

(In the original question, the word spending was missing and had to be determined.)

This question featured in a recent (April 2018) edition of the UK TV programme Have I Got News For You, quoting a question from the quiz programme University Challenge (because the guest host of the former – Jeremy Paxman – is also the regular presenter of the latter).

I correctly guessed that the missing word was spending, and then, working with the (perhaps simplistic) rule that "a gerund is a noun made from a verb" thought: is this really a gerund? In, for example, "This month's spending has increased", spending would, I believe, be correctly labelled as a gerund (spending acts as a noun; the amount of spending that occurred this month). In the above case, however, it feels like it is still being used as a verb.

Doing some research, the most helpful resource I came across was Gerunds, participles and forms in -ing from Linguapress.com. This lists four different types of words ending -ing:

1. The gerund is a verb which is used as if it were a noun. Since it is a verb, it can not be qualified by an adjective, nor preceded by an article, but it can be modified by an adverb and take a complement.

   
   
   
   
   
   
   • Seeing is believing.
   
   
   • Living cheaply in New York is quite possible.
   
   



2. A verbal noun is a noun formed formed from a verb; some of these end in -ing. It can take a determiner, and be qualified by adjectives.

   
   
   
   
   
   • The book was easy reading!
   
   
   • He managed to make a good living.
   
   




3. A participle is an adjective or part of a participial phrase qualifying a noun or a pronoun.

   
   
   
   
   
   • Smiling, the lady told them they'd won the big prize.
   
   
   • I heard them arguing last night.
   
   



4. The present participle is also used in the progressive aspect of verb tenses.

   
   
   
   
   
   • I'm taking my brother to the station tonight.
   
   
   
   • The man was phoning his friend, when the lights went out.
   
   

To my (imperfect) understanding, in "Riches are for spending.", I don't believe spending fits cases (1) or (2) since I don't think it is being used as a noun. Neither does it seem to fit case (3), since it isn't modifying a noun. It does seem to fall into the fourth category – the progressive aspect – as it represents an ongoing action: spending money (riches). (One might have written "Riches are to be spent." – which [to me] reinforces that it is being used as a verb.)

If the question had come from almost any other quiz show, I would probably have just assumed I was right and chalked it up as a (minor) error on the question-setters' part. However in this case:

1. University Challenge is quite a "high-brow" quiz ... as can be seen from the other questions in the book listed above. While it doesn't exclude "popular culture", the bulk of its questions are of university-level across many subjects including classics, history, biology, physics, chemistry and the arts. As the book's introduction says: "[The question setters'] hard work – fact-checking, double-checking, cross-checking, and verifying – is contained in these pages.".

   
   
   

   In other words, I would not expect them to be wrong (although I'm sure it has happened).




2. Especially in the light of the above, I am in no way certain of my analysis, and would welcome an explanation of why the word is, in fact, a gerund.

The closest on-site question I could find is When does a gerund become a verb?. This clarifies that a gerund doesn't become a verb (under certain circumstances), but that a word ending -ing might be a verb. Unfortunately, the answers don't help me clarify the question (but suggest a third option: the use of spending in the original quote may be ambiguous, and there is not enough context to determine if it is being used as a gerund or not).

I don't believe the answers to What's the difference between a gerund and a participle? cover this case: partly because that covers cases (1) and (3) above, but I believe this use is between cases (1) and (4) – gerund or present participle/progressive aspect. However, the accepted answer there (and comments to it) show how complex and/or a matter of opinion these distinctions are, so it may be that this is too "opinion-based".

So: is spending in "Riches are for spending" (a) a gerund, (b) one of the other types of "-ing" word, or (c) we cannot tell from the context?

Answer

Riches are for spending.

I take "spending" as a verb here (cf. "riches are to spend"). Syntactically, there are several indications that it's behaving as a verb:

[1] it can be modified by an adverb: "Riches are for spending extravagantly/cautiously/recklessly", whereas nouns cannot (normally) be modified by adverbs.

[2] Unlike nouns, it has no plural form - we can't say *"Riches are for spendings".

[3] It can take a to PP complement: "Riches are for spending on luxuries".

Traditional grammar analyses "spending" here as a gerund simply because it is complement of a preposition, i.e. a location where nouns normally hang out. Which doesn't tell us what part of speech it actually is -- a typical weakness of traditional grammar.