It is rational to be emotional

Contrary to the classic view of emotions being antirational, a fully rational human would feel life strongly

I have been on a decades-long journey to understand what it means to be rational. This could be part of why I became a scientist. I’ve been doing this partly out of intellectual curiosity, but also out of a belief that I can improve my life (and the lives of those around me) by making better decisions.

Perhaps the deepest insight I’ve achieved so far is that optimal rationality is defined by emotion. Which means (among other things) that it is rational to have fun.

I’m not just saying that rationality is compatible with emotion, but something much deeper. For humans, it is clear that what we are optimizing for by being rational are positive emotional states.

This has to do with us being fundamentally goal-seeking creatures. At our most fundamental level we seek reward and avoid pain/punishment, such that optimal decisions are those that optimize rewarding states. We experience rewarding states as emotions, such that being rational is defined by feeling (or seeking to feel) desired emotion. This idea is highly related to philosopher David Hume’s statement that “reason is, and ought only to be the slave of the passions”.

In retrospect this logic seems obvious, so why does this insight still seem surprising (to me at least)? It’s largely because there is another definition of rationality: Optimizing for accurate knowledge of the world. This reflects the fact that there are two forms of rationality (see Stanovich, et al. 2016) that are usually compatible but not always. The form that seeks reward is called instrumental rationality, while the form that seeks accurate knowledge is called epistemological rationality. Emotions often get in the way of epistemological rationality, but they are the entire point of instrumental rationality

It turns out that humans are primarily instrumentally rational, with epistemological rationality taking a back seat. The point of science is to prioritize epistemological rationality, which I think is why emotional suppression is associated with science and rationality. Basically, while learning about the world we would optimally become “disinterested” in which of several hypotheses turns out to be true, so we can (try to) avoid bias while conducting science or evaluating beliefs generally.

However, once we have a clear answer, I think it makes all the sense in the world to feel strongly about what we learn. Further, it is fully rational to experience strong curiosity regarding what the answer might be, so long as we’re not biased toward (or away from) a particular outcome.

In the course of living life the pull toward emotion should be embraced even by the intellect, as it is the very point of it all. Only on those very important occasions where we wish to learn about the world should we discipline our passions to see how the world truly is. Of course, the main reason to learn about the world is so we can better navigate it in pursuit of rewarding emotional experiences. So, the ultimate point of science and rationality is to have better emotional experiences (more joy, less pain) as we live our lives.

[Fun fact: The artwork at the top was generated using the AI-based art generating tool DALL-E 2]