Section 14 Group 3: Popper and Kuhn

On Tuesday, we are talking about Karl Popper and Thomas Kuhn. Both of these philosophers talk about philosophy and science. Popper thought that scientists learn more from trying to prove their hypotheses false instead of trying to prove them correct. The example in the book was trying to the hypothesis "all swans are white" to be correct. If you were to simply observe a bunch of swans and note that they are all white, you still can't say that "all swans are white" because until you see every single swan on Earth, and prove that they are all white, you can't truly say that "all swans are white." All it would take would be one black swan and the hypothesis is false. This is the Principle of Induction. Arguing from a selection of observations to a general conclusion. According to Popper, science doesn't rely on induction. Scientists start with a hypothesis and then find a way to test that hypothesis, meaning that they want to prove that the hypothesis can survive attempts to falsify it. Because falsifying a hypothesis will give us new information, while trying to prove a hypothesis correct merely gives us an idea that could potentially be disproved at any given time.
In biology, when you want to test something you have a null and an alternative hypothesis. The null hypothesis is the idea that changing something will have no effect on the outcome and this is the one you try to prove. For example, I'm starting a project for my ecology class this week about the effects of capsaicin (the stuff that makes peppers hot) on bird nest predation. The null hypothesis is "capsaicin has no effect on bird nest predation." This is what we are trying to prove is true. The alternative hypothesis is "capsaicin has an effect on bird nest predation." So if we fail to reject our null hypothesis (we never accept a hypothesis because it can be disproved later) then we know that there isn't an effect of capsaicin on predation. As opposed to rejecting the null hypothesis and having to continue studies with capsaicin effects on different kinds of nests, different locations, different predators, etc. We would learn more failing to reject the null hypothesis than actually rejecting it.
Kuhn talked about "normal science" and "paradigm shifts." He said that there aren't facts waiting to be discovered, but rather the paradigm or framework somewhat fixes what you can think about. Like the idea that the sun revolves around the Earth. Because this was the belief, any evidence to the contrary was thought to be mistaken. Paradigm shifts occur when a whole way of understanding is overturned, like going from the idea that the sun revolves around the Earth to the Earth revolves around the sun.