I am into finding a convincing formula, or at least a rule of thumb, about when to use "to" and when to use "for" after adjectives - such as easy, difficult, important, interesting, and useful - and before personal pronouns and nouns.
I have gone through numerous and different advice by English-speaking people on the "to vs. for" problem for non-English speakers.
There were some cases in which they seemed interchangeable while there were others where they did not. Many people said the issue could be more about a preference or tendency than a rule, thus leaving English learners no choice but to learn them case by case. I came across some advisers who came up with a few rules, some of which I found very helpful while others seemed to contradict one another.
In the following examples, "to" and "for" seem to be interchangeable, and yet slightly different in meaning.
I reason that a marked difference between "to me" and "for me" would be found in whether "me", the narrator, has experienced it, the subject of the sentence, or not.
(A) English is not easy "to me".
This implies that English is not easy "in my view (in the view of the narrator)".
(B) English is not easy "for me".
This implies that English is not easy "in my experience (in the experience of the narrator)".
How does my reasoning sound to you? Any comments will be greatly appreciated.