There is little you can predict. Rather, you can predict all you want, but accuracy is another matter. You cannot accurately predict how someone else will react to anything any more than you can predict how you will. And what is the value of predicting? Predicting is some kind of squinting your eyes and calculating the odds.

And when you calculate, and your calculation is accurate, what is so marvelous about that? What has been accomplished? What is so tremendous about being correct once or twice or ten times?