Quassim Cassam explores epistemic vices in his book Vices of the Mind to understand how certain vices can obstruct knowledge and why they matter. Such vices tend to be thinking vices, that is vices that relate to the way we think about and understand the world. They may impact how we view and perceive the world, how we communicate information, or whether we are able to retain and recall information when needed. For example, being closed-minded can inhibit us from taking in an accurate view of the world, being arrogant may prevent us from effectively communicating knowledge about the world, and being careless or easily distracted may limit our ability to remember and recall information.
However, some epistemic vices can also be understood as character vices. Cassam writes, “character vices actually have a dual use: they can be used to characterize a person or they can be used to describe their thinking, either in general or in a particular case.” Character vices are not just behaviors, but ways of being that are typical for a person, that embody some essential aspect of an individual. Instead of just describing an action or behavior to understand its consequence, we can use character vices to understand an entire string of behaviors and actions of an individual, to understand their larger life outcomes.
Wishful thinking is a good example of a character vice that can have dual use. If you watched more college basketball than normal over the course of the pandemic, then by the time the NCAA Tournament started, you may have engaged in wishful thinking, placing a larger bet than you should have on the outcome of some of the games. But being overconfident in a couple of bets and believing that the best possible outcome would truly come to pass is different than being characteristically a wishful thinker. Someone who we describe as a wishful thinker is likely to always see the upsides and believe that things will work out as desired. As a result, they may not be prepared when things go wrong, and may not be able to overcome or avoid obstacles.
Wishful thinking as an epistemic character vice can describe your individual action or it can describe you as a person. Either way, it is helpful to see that epistemic vices can operate on multiple levels. Studying epistemic vices so closely helps us understand our thinking, our behaviors, even our personalities. They help us connect specific behaviors or traits to real-world outcomes, hopefully allowing us to see the harms that can come from actions, behaviors, and traits that obstruct knowledge.