質問: 逃げる以外**に**方法がない。 逃げる以外**で**方法がない。 I know the sentence means roughly 'There is no other way except to run away' (per this site; ), but I don't understand what would be the difference in alternating between these two particles. Can't they both 'adverbialize' a noun? I just want to better understand the nuance between で and に when they are modifying a verb.
回答: When a word takes で even without 以外, it still takes で with 以外: * 現金以外で支払えますか? * 東京以外で働きたい。 * 炊飯器以外でお米を炊く方法 Notice that we can say 現金で支払う, 東京で働く, 炊飯器でお米を炊く. This explains 病気などの理由以外で, too (理由 safely takes で). Next, what about 逃げる以外で? 逃げるで of course makes no sense because 逃げる is not even a noun. This type of で is a kind of condition marker, and 逃げる以外で sounds like you are imposing some constraint on your request/question. Something like this is perfectly fine: * 逃げる以外で何か方法はありますか? (逃げる以外に is also fine) * 逃げる以外で対策を考えよう。 (逃げる以外に is acceptable but less natural) * お勧めの観光地を教えてください。京都以外で。 (京都以外に sounds weird) However, in your case, the sentence is not asking for something in the first place, so 逃げる以外に方法がない sounds more natural to me. Other examples where に is more appropriate: * 大学に入ったら運転免許以外にノートPCも欲しい。(運転免許以外で is acceptable but less natural) * 日本語を学ぶなら漢字を覚える以外にない。(漢字を覚える以外でない is wrong)