Alexander the Great 's horse.
Plutarch wrote:
Philonicus the Thessalian brought the horse Bucephalas to Philip, offering to sell him for thirteen talents; but when they went into the field to try him, they found him so very vicious and unmanageable, that he reared up when they endeavored to mount him, and would not so much as endure the voice of any of Philip 's attendants. Upon which, as they were leading him away as wholly useless and intractable, Alexander, who stood by, said, "What a magnificent horse they lose, for want of address and boldness to manage him!" Philip at first took no notice of what he said, but when he heard him repeat the same thing several times, and perceived that he was much vexed to see the horse sent away, he said to him, "Do you reproach those who are older than yourself, as if you knew more, and were better able to manage him than they?" "I could manage this horse," replied he, "better than others do." "And if you fail," said Philip, "what will you forfeit for your rashness?" "I will pay," answered Alexander, "the whole price of the horse." At this the whole company fell to laughing; and as soon as the wager was settled amongst them, he immediately ran to the horse, and taking hold of the bridle, turned him directly towards the sun, having, it seems, observed that he was disturbed at and afraid of the motion of his own shadow; then letting him go forward a little, still keeping the reins in his hand, and stroking him gently when he found him beginning to grow eager and fiery, he let fall his upper garment softly, and with one nimble leap securely mounted him, and when he was seated, little by little drew in the bridle, and curbed him without either striking or spurring him. Presently, when he found him free from all rebelliousness, and only impatient for the course, he let him go at full speed, inciting him now with a commanding voice, and urging him also with his heel. Philip and his friends looked on at first in silence and anxiety for the result, till seeing him turn at the end of his career, and come back rejoicing and triumphing for what he had performed, they all burst out into acclamations of applause; and his father, shedding tears, it is said, for joy, kissed him as he came down from his horse, and in his transport, said, "O my son, seek out a kingdom worthy of thyself, for Macedonia is too little for thee."