In “Nahjul balagha” (sermon 163) you can read that when people went to Amir al-mu’minin in a deputation and complained to him through what they had to say against `Uthman, and requested him to speak to him on their behalf and to admonish him for their sake, he went to see him and said:

by Allah, I do not know what to say to you. I know nothing which you do not know, nor can I lead you to any matter of which you are not aware. You certainly know what we know, we have not come to know anything before you which we could tell you; nor did we learn anything in secret which we should convey to you. You have seen as we have seen and you have heard as we have heard. You sat in the company of the Prophet of Allah as we did. (Abu Bakr) Ibn Abi Quhafah and (`Umar) ibn al-Khattab were not more close by acting in accordance to truth than you, since you are nearer than both of them to the Prophet of Allah through kinship, and you also hold relationship to him by marriage which they do not hold.

Discussion:

This speech contains some major refutations to modern shia faith.

1) Words of commander of faithful:

I know nothing which you do not know, nor can I lead you to any matter of which you are not aware. You certainly know what we know, we have not come to know anything before you which we could tell you; nor did we learn anything in secret which we should convey to you.

These words are great proof for fact that Ali wasn’t more knowledgeable than Uthman! Because he said: I know nothing which you do not know. It is so obvious, that translators of this speech to English have to corrupt it by inserting phrase (in this matter), between I know nothing and which you do not know.

2) From text is also clear that in the view of sayidina Ali, sheykhan were acting in accordance to haq! And they didn’t surpass Uthman in that!

Of course shias as usual would claim that this was taqqiyah and etc. But who cares about their words?

3) Also in this speech is clear proof that prophet (sallalahu alaihi wa ala alihi wa sallam) didn’t teach anything to Ali, what he didn’t teach to others! And that in his words: nor did we learn anything in secret which we should convey to you

4) It’s clear that all those lunatics with turbans on their empty heads, lied and deceived their followers, when they claim that prophet (sallalahu alaihi wa ala alihi wa sallam) didn’t have daughter except Fatima! Because Ali here pointed to marriages of Uthman, which married twice on the daughters of prophet (sallalahu alaihi wa ala alihi wa sallam).