Alexander, there's another ancient law of kingship: to trust no one, and to learn how to be alone.
— Philip Ii Of Macedon (Fredric March)
16 seconds sound clip from the Alexander the Great (1956) movie soundboard.
You can hear this line at 00:30:50 in the Blu-ray version of the movie.
Quote context
[...]
- With this seal, you rule in my absence as though you were king.
- You have the power to collect taxes, raise troops, make war and hold royal court.
- For as it is with the king, according to ancient Macedonian law, so it is with his regent.
- He is, in his single person, lord of all things, both open and secret, at once general and absolute.
- I am leaving Antipater here as your adviser.
- Alexander, there's another ancient law of kingship: to trust no one, and to learn how to be alone.
- No.
- Not because he wanted it so, but because he had no choice.
[...]