How do Scientists (particularly social scientists) know which variables to control for, and which not to?
Suppose I for some reason had the hypothesis that people with lower empathy made better businesspeople and I conducted some research and controlled for socio-economic background. If my hypothesis was correct but low empathy was also heritable and this meant lower empathy people were more likely to have higher socio-economic backgrounds then I might find no relationship. Isn’t this a problem, ie controlling for a variable meant I got the wrong result? What am I missing?