As a general rule, under the vassalage-and-manorialism system (which is often referred to simply as "feudalism," even though that's only the vassalage part), you couldn't just pay extra money and suddenly have a better title. I won't, at all, pretend like that never
happened in European history because if I do, I am 110% certain to get at least two people "um akshully"-ing me about it. But as a general rule, the whole point of these titles was fealty and establishing a baseline of legitimacy; being able to simply pay some money and suddenly you're now a duke isn't really compatible with that. (Likewise, the story above of the guy who became duke by fiat declaration--such things were rare because few people had the clout to make such a play, and fewer still had the clout and military power
to pull it off.)
That said, a sizable contribution to one's liege lord is a good way to persuade them to create
a new title for you--the trick is to make sure the rest of the aristocracy accepts it, and that you get concomitant benefits for it. Being named Duke of Nowheresville, population -12, net income three feathers and one pretty shell, vassals including the birds from which the feathers fell? Not particularly useful, and indeed bordering on a slap in the face. As a general rule, being a Baron means you're the vassal of either an intermediate ruler (e.g. a Count(ess)/Earl, Viscount(ess), or possibly Prince(ss)), or of the top-level ruler for your country (generally, some form of Duchess/Duke or King/Queen.) So if you're paying money to get a "promotion," you're either bypassing the person you report to and currying favor with their boss
(a great way to make an enemy, even if you succeed), or you're basically saying that the big boss of all your fellow "employees" should give you special favors because you bribed them.
Note, again, this doesn't mean it can't
work. It just begs the question: why doesn't everyone do this? There are lots of potential answers, some of them favorable, some unfavorable. Many of them don't really make sense unless you just don't care about suspension of disbelief, e.g. "nobody ever thought to do it before!" is a bit of a hard sell in a kingdom with more than a century or two of history, so you need to consider carefully how to proceed. Possible options include (but are not limited to):
- It just doesn't work that way in this feudal structure, sorry!
- Such promotions are considered unseemly, and will result in social ostracism (though there may be other ways to deal with that, too)
- People have already taken advantage of this--a lot. There are no existing titles to be promoted into, because other families have already bought their way to the best titles available.
- A bought title is empty--it confers no real power or authority, the buyer is expected to turn it into something useful on their own.
- A bought title is always at the frontier, with the expectation that the buyer will transform it into a loyal, productive, taxable plot of land.
- Buying a new title is a lengthy and difficult process and not everyone qualifies.
- You can only buy a better title once you have done a service to the Crown. Higher titles require both more money and a more significant service rendered.
- You have to gain recognition from some other thing in order to buy a title. E.g. you must serve in the army and achieve a certain rank, or you must gain a diploma from the royal university and publish a productive scientific work, or you must create a corporation that employs a certain number of people in the Capital, etc.
Most of these limitations come in the form of "you must complete X difficult task first," "you must work to make the title actually matter," or "there are hidden costs to doing this that must also be dealt with."
Wasn't it Herark the Harbinger who once said that, to deal with messages such as this, we should make it declare its obverse?
So 'Nothing stops him' would become 'Something does not stop him', and, again, 'Nothing does stop him.'
Therefore, what is the 'Nothing' that stops him? What or where is 'Nothing'?
What does this even mean?