there is a difference between the genus and the necessary in reality although they do not differ in generality according to what is known in logic. the essential genus is the general that is said in response to what it is and enters into the essence of the limited thing and is a component of its essence. so the fact that man is alive is included in the essence of man i mean animality so it is a genus. and his being born and created is necessary for him and never leaves him but it is not included in the essence.
وفرق بين الجنس واللازم في الحقيقة وإن لم يفترقا في العموم على ما عرف في المنطق، فإن الجنس الذاتي هو العام المقول في جواب ما هو ويدخل في ماهية الشيء المحدود ويكون مقوما لذاته. فكون الإنسان حيا داخل في ماهية الإنسان أعني الحيوانية فكان جنسا. وكونه مولودا ومخلوقا لازم له لا يفارقه قط ولكنه ليس داخلا في الماهية.