Hayy Observes the Difference Between the Animals and Himself
Moreover, he observed that his fellow-fawns began to have little horns which they had not had at first; and while they were at first weak, and unable to run far, yet in progress of time grew to be very vigorous and nimble, and active in their movements. But none of all this he perceived to befall himself, and as often as he pondered over the matter, he could not make out what should be the reason thereof.
Also, when he beheld the creatures such as had any fault or defect of limbs, he could not find one amongst them like himself. All these matters evoked great grief and anxiety within him; and after having earnestly pondered over the matter and perplexed himself therewith, he at last gave up, in utter despair, the hope of being supplied with that, the want of which so sorely troubled his mind.