English adverbs - why does "foreseeably" exist, but "unforeseeably" doesn't?
In an essay I talk about groups changing - they do so in an unforeseeable manner. So I wrote the following sentence: "This works specifically well in dynamic environments where the groups change fast and unforeseeably. "
Now, I know that "fastly" for example is outdated (source: http://www.dictionary.com/browse/fastly), so I know not all adverbs exist, and usually I have a good intuition.
But with "unforeseeably" I can't seem to decide whether it sounds right or wrong. "Oxford dictionaries" says it doesn't (by redirecting me to unforeseeable): https://en.oxforddictionaries.com/definition/unforeseeably Foreseeably, however, seems to exist: https://en.oxforddictionaries.com/definition/foreseeably
Another example, I know that wirelessly exists, but wiredly doesn't (again, checked here: https://en.oxforddictionaries.com/definition/wiredly).
Do you agree that unforeseeably can't be used? How could I know without learning all adverbs by heart? Is there any rule of thumb?
"Unforeseeably" sounds fine to me, the full Oxford English Dictionary is happy with it, and Google finds it in multiple articles from major British and American broadsheet newspapers over the last twenty years.
In general, though, there's no cast-iron way to declare an English word "allowed" or "disallowed". There's no final authority, and of course appropriate language depends heavily on the medium and the audience. In a simple children's book I wouldn't use "unforeseeably" but for an academic essay (which seems to be what you're working on here) it's appropriate.
Thank you for your response. What a simple yet effective idea to just google it, I'll definitely do that when in doubt next time.
Sure, it always depends; but I would claim that some words are just not used (anymore) and thus "disallowed". Frankly, a lot of the academic papers I read contain outright English mistakes, so it's not like anybody cares whether "unforeseeably" exists or not when they read mine. And none of my supervisors are native speakers, so they probably don't know exactly, either. Still, I was curious. :-)
Yes, I agree that some words would be almost unanimously regarded as wrong or non-existent -- but there's a huge grey area of words which are listed in some dictionaries and used by some people, but unfamiliar to others.
Google (and text searches in general) are generally excellent arbiters in a case like this. As well as google searches restricted to e.g. respectable news sources, you can use Google Books, Trends, and ngrams to get a feeling for where, how, and when terms were/are used. There are also free online English corpora to search, and of course for technical terms you can search downloaded PDFs of papers in your field (or full-texts online via Google Scholar, etc.).
And none of my supervisors are native speakers, so they probably don't know exactly, either.
And of course many native English speakers, including university students up to postgraduate level, also write terribly...
I think the questions you need to answer are will your audience understand you, what kind of opinion will they form about you based on your word choice, and is that the kind of opinion you want them to have?