In several answers in AskPhilosophers, philosophers say that some uttered words express emotions, feelings, sensations and the like (but you always use the word "express"), and that this is not the same as some words saying or stating that such emotion (etc.) occurred. So you make a big difference between expressing and saying (or perhaps stating). For instance, "ouch" expresses pain, while "I am feeling pain" states that such pain exists. Sometimes you say that expressing cannot be true or false, but statements can. It is very difficult for me to understand this difference. I understand that "ouch" is much more immediate than "I am feeling pain", and that "ouch" is slightly humorous, and there may be other differences, but basically these two sentences just say the same thing. They convey the same basic information and both can be used to give a false information. Would you be so kind as to explain me what is the difference between expressing and saying (stating) in cases where what is expressed can be said (stated)?

A very interesting question touching on complicated territory! Probably the best response I can give is to recommend the SEP article on "Pragmatics," available at this link. I think you'll find it contains lots of information highly relevant to your question.

Read another response by Stephen Maitzen
Read another response about Language, Emotion