3 ms·

You have to hypothesise both A and not-A. If you can rule out A then you know not-A is true. (Or you reject the Law of the Excluded Middle, but that's not cool

by Y_Y 5y ago

You have to hypothesise both A and not-A. If you can rule out A then you know not-A is true. (Or you reject the Law of the Excluded Middle, but that's not cool.)

mjfl 5y ago
Well really the hypotheses are "A causes B" and "not A causes B" which does actually leave a third case "A and B are independent".
- mhio 5y ago
  Which leaves a rather large set of N causes B's