MORE INFO
In an effort to make my question as short as possible, I abbreviated too much. This is the complete sentence that originated my question:
少年時代から20年間もずっと過ごしてきて、他人から軽んじられるのに慣れていなかった。
Now you can see what I clipped. I removed important information. This question is answered. My mistake. I answered my own question to clear this up. Sorry I caused so much confusion. But, this was very instructive for meI've learned how to ask questions better.
ORIGINAL QUESTION
(1) イギリス人に軽{かろ}んじられた。
(2) イギリス人から軽んじられた。
Both appear to be grammatically correct 受{う}け身形{みけい} and also have the same meaning:
"I was looked-down upon by English people."
(3) 虎に食べられた。
Appears to be grammatically correct 受け身形 and mean:
"I was eaten by a tiger."
So, if I can swappedswap "から" for "に" in #1 and #2, can I do the same with #3 and say:
(4) 虎{とら}から食{た}べられた。
#4 does not sound possible to me (but maybe it is?).
So, might it be that "に" is the standard/naturalsafe thing to use in 受け身形?
Sometimes, "から" can be swapped in for "に", but in reality you'd need a native ear to sense when that is appropriate?