>"If we make it to Friday morning without a test..." and this argument is simply FALSE. It's about something not possible. It is like saying "If 1 = 2..." Well

>"If we make it to Friday morning without a test..." and this argument is simply FALSE. It's about something not possible. It is like saying "If 1 = 2..." Well, yes it is like saying "if 1=2, then 2=4", but that doesn't mean that this line of thinking is an invalid one. It simply means that by showing the result to be wrong, the test at the start is also wrong. The statement isn't attempting to prove that 2=4 by assuming that 1=2. It's saying that we can show that 1 quite clearly doesn't equal 2 because the logic consequence of that would be wrong. In the same way "If we were able to make it to Friday without a test, then we'll know that the surprise test is Friday" isn't an invalid line of thinking. It's simply showing that it can't be possible for the surprise test to be on Friday.