As a public speaker you can assist this emphasis of contrast with your voice. If you say, "My horse is not _black_," what color immediately comes into mind? White, naturally, for that is the opposite of black. If you wish to bring out the thought that destiny is a matter of choice,you can do so more effectively by first saying that "_DESTINY_ is _NOT_a matter of _CHANCE_." Is not the color of the horse impressed upon us more emphatically when you say, "My horse is _NOT BLACK_. He is _WHITE_"than it would be by hearing you assert merely that your horse is white?
It would be a boon to speech-making if speakers would conserve the attention of their audiences in the same way and emphasize only the words representing the important ideas. The average speaker will deliver the foregoing line on destiny with about the same amount of emphasis on each word. Instead of saying, "It is a matter of _CHOICE_," he will deliver it, "It is a matter of choice," or "_IT IS A MATTER OFCHOICE_"--both equally bad.
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