从前文后理来推断一个字的意思。

I don’t know what’s going on in this part of the sentence: 从前文后理. Would love if someone could break it down for me.

Hi, bit late, but pretty sure it’s a typo. 前后文 = context (in a written text). Such that it would say: 从 (from) + 前后文 (context). 理 might be ‘meaning’ (from the context’s meaning), then 推断 is to infer, and the 来 is some sort of connector between the two parts of the sentence. “From context’s meaning [来 go to] infer a character’s signification.”