Now, what you want is an alternative hypothesis. The hypothesis is, no, I think the drug actually does do something. So the alternative hypothesis right over here is that the drug has an effect. Or another way to think about it is that the mean does not equal 1.2 seconds when the drug is given. So how do we think about this? How do we know whether we should accept the alternative hypothesis or whether we should just default to the null hypothesis because the data isn't convincing? And the way we're going to do it in this video, and this is really the way it's done in pretty much all of science, is you say, OK, let's assume that the null hypothesis is true.