PPL 212 Lecture Notes - Lecture 21: Foodborne Illness, The Bellevue-Stratford Hotel, Sexually Transmitted Infection
Document Summary
The need for a control: to know that x causes y we must know . What happens when x is absent (and all relevant conditions are the same as when x was present: in other words, we need a control case. Background knowledge: these tests take place against he background of normal conditions and context, what counts as a normal context varies, we must use common knowledge. Practice: what is x? what is y, what information is needed to determine whether x causes y, 1. Info needed to verify: control group with one side drinking coffee and another not and measuring their growth over time. Almost everyone at the food and not everyone came down with the pneumonia. Lessons of causal reasoning: causal reasoning shows us. 1. there is a complicated interplay between what is already established and what is being tested. Induction is falliable (but we need these tests to have any guidance at all)
