My top 10 highlights from the book: 

1. No trait of Alexander's was more firmly held or enduring than his admiration for genuine excellence and brilliant achievement.

2. Stand firm, for it is toil and danger that lead to glorious achievements.

3. True men need no reward for their labors aside from those labors themselves, as long as these have noble consequences. 

4. Philip [Alexander's father] considered that the task of training and educating his son was too important to be entrusted to the ordinary run of teachers.

5. Fortune generally makes those whom she has compelled to put their trust in her alone more thirsty for glory than capable of coping with it.

6. He was devoted by nature to all kinds of learning and was a lover of books. 

7. Alexander had incredible mental energy and almost excessive tolerance of fatigue.

8. Nothing put him off. In spite of everything, Alexander just kept coming on and on. The freezing cold and the starvation made it a tremendous task, but they couldn't stop him. And in the end his enemies were struck with fear and amazement at the speed of his advance.

9. I would rather excel the rest of mankind in my knowledge of what is best than in the extent of my power.

10. It is my belief that never in the world was there another like him.