ЖЕ vs И И and же can both add emphasis, but the kind of emphasis is different. И usually emphasizes that something is exactly the expected, logical, or relevant result. It often has the meaning "indeed", "actually", "exactly", "and that is what happened." Он и пришёл. - He did come / And he actually came. Я так и думал. - That's exactly what I thought. Он это и сказал. - That's exactly what he said. Я этого и хотел. - That's exactly what I wanted. Here и focuses on the element that completes or confirms an expectation: Я хотел поговорить с ним. Я ему это и сказал. I wanted to talk to him. And that's exactly what I told him. Же works differently. It usually points back to something that should already be obvious, known, remembered, or accepted. It can express insistence, contrast, impatience, correction, or "after all / you know / indeed." Я же сказал тебе! - I told you! / I did tell you! Он же врач. - But he's a doctor! / He's a doctor, after all. Это же невозможно! - But that's impossible! / That's obviously impossible! Ты же знаешь. - You know that. Compare: Я это и сказал. That's exactly what I said. Я же это сказал. But I told you that! / I did tell you that! The first sentence with и identifies what was said: "that is exactly what I said." The second with же reminds the listener of something they should already know: "I already told you that." Another comparison: Он и пришёл. He actually did come / He came, just as expected. Он же пришёл. But he came! / He did come, remember? So they are not interchangeable. A useful rough distinction is: и = "exactly that / indeed that / that is what actually happened" же = "but / after all / as you know / I am reminding or insisting" Also, emphatic и often works as part of common constructions such as: так и... : Я так и знал. - I knew it. вот и... : Вот и всё. - That's it. именно ... и... : Именно это я и хотел сказать. - That's exactly what I wanted to say. Же is much more connected with the speaker's