عَنْ عَلِيٍّ رَضِيَ اللَّهُ عَنْهُ قَالَ أُهْدِيَ لِرَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَآلِهِ وَسَلَّمَ بَغْلٌ أَوْ بَغْلَةٌ فَقُلْتُ مَا هَذَا قَالَ بَغْلٌ أَوْ بَغْلَةٌ قُلْتُ وَمِنْ أَيِّ شَيْءٍ هُوَ قَالَ يُحْمَلُ الْحِمَارُ عَلَى الْفَرَسِ فَيَخْرُجُ بَيْنَهُمَا هَذَا قُلْتُ أَفَلَا نَحْمِلُ فُلَانًا عَلَى فُلَانَةَ قَالَ لَا إِنَّمَا يَفْعَلُ ذَلِكَ الَّذِينَ لَا يَعْلَمُونَ
It is narrated from Sayyiduna Ali (may Allah be pleased with him) that a male or female mule was given as a gift to the Messenger of Allah (peace and blessings be upon him). I said: What is this? The Prophet (peace and blessings be upon him) said: This is a male or female mule of the breed. I said: How is it produced? The Prophet (peace and blessings be upon him) said: When a donkey mates with a mare, this is produced from them. I said: Then should we not mate such-and-such donkey with such-and-such mare? The Prophet (peace and blessings be upon him) said: No, only those people do such a thing who do not have knowledge.