Why is theory important?

Nowadays more information become available and more accessible, big data analysis becomes very popular. Sometimes people can spot a phenomenon first through data analysis, then try to create a theory to explain this phenomenon. However, sometimes people use empirical study and/or experiments to test whether a newly developed theory works in the real world or not. Therefore, we can say that there is an undirected link between theory work and empirical work (and experiment work).

Theory is very important for us to understand the world. It helps us to understand the world. Theory and model often simplify the real world problem. More importantly, theory can help us to open the black box. When we observe a relationship between two objects, it is hard for us to draw a conclusion about the causality behind the relationship; then here comes the help from theory. From the mathematics and logic inside theory, people can understand the phenomenon better.

However, it does not mean theory is always correct. Especially in social science, for one thing, there are multiple theories to explain; all the theories seem legit. Sometimes theories are different because they are looking at the problem from different angles; sometimes they are different because they include various factors. When we face such differences, we do not need to worry too much, we just need to apply different theories based on the circumstances we face. However, when the logics behind them are different, then we should be very careful, because the two theories are possible to contradict each other.

Machine learning and other methods may be able to help us to solve problems, but theory will help us to look into the black box and gain better understanding.