This hadith has been reported by Mansur with the same chain of transwitters and he said:

" He should aim at what is according to him correct."

وَحَدَّثَنَاهُ يَحْيَى بْنُ يَحْيَى، أَخْبَرَنَا فُضَيْلُ بْنُ عِيَاضٍ، عَنْ مَنْصُورٍ، بِهَذَا الإِسْنَادِ وَقَالَ ‏

‏ فَلْيَتَحَرَّ الَّذِي يُرَى أَنَّهُ الصَّوَابُ ‏

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