I complained that we talk a lot about critical thinking without telling people what or how to exercise critical thinking. So I wrote a quick tutorial
Critical thinking is having good skepticism. We strive for a golden mean: we don't accept everything as true, but at the same time we don't reject everything as false. This sounds reasonable, yet it is hard to do in practice.
The main problem is our cognitive bias towards believing arguments and evidence that confirms our ideas while rejecting those that disagree with them. We don't only reject ideas, but we will reject people who hold different opinions. If we happen to be right, then this behavior keeps us from being wrong. Yet if we are wrong, we dig ourselves deeper into error.
We must remember that it is not possible that we are right most of the time. The human condition is one of ignorance and error. At best, we should know that we will be wrong about half of the time. It is more reasonable to expect that we are right less than that. Critical thinking is about being humble and keeping our ignorance and fallibility in mind.
Critical thinking is then a way to protect ourselves from misleading ourselves.
Critical thinking is about asking questions to determine if we are wrong. It is often hard to prove we are right. It is a lot easier to check if we are wrong. So, the starting question for critical thinking is asking the question:
"Am I wrong about this?"
Once we ask ourselves this question, we can expand it to a small set of follow-up questions:
"Is it logically invalid?"
"Is the evidence false?"
"Does it go against the majority of experts?"
You may decide that you are still in the right. Double check on your conclusions by asking yourself
"Do I really want to believe this is true?"
Today, this is the core question that we have to answer ourselves. The biggest danger is wanting to convince ourselves. We are the best at persuading ourselves, especially when we deeply want it to be true.
Critical thinking involves a lot of emotional intelligence. Most of us get agitated if we are exposed to some ideas that we disagree with. We need to acknowledge our emotions to be able to consider that we may be wrong. Sometimes understanding that we are wrong comes along with sadness and anxiety. These emotions along with uncertainty can be disquieting. Yet in many cases, knowing that we don't know is the best we can do with the evidence we have available. Certainty is soothing, which makes it attractive, even when it is false. Acknowledging uncertainty and living with it is a sign of exercising critical thinking.
Always consider that we may be wrong. Even after we asked ourselves these questions, and it appears that we are right. All conclusions are temporary until we have more evidence or a fresh perspective to consider our beliefs.
Learning more logic, probability, and how evidence works will improve your abilities to tease out if we are wrong. Learning about what are the common ideas in a field with help you catch up quickly in areas where one is ignorant. Reviewing cognitive biases and informal logical fallacies will guard us against psychological tricks many use against us; or worse, that we may use on ourselves.
Remember that we live in an adversarial information age. Marketing and propaganda surround us, trying to change our behavior for profits or politics. They will tell us how smart and beautiful we are, show us what we believe and tell us how true it is, and then do a subtle nudge to where they want us to go. For this reason we need to be especially aware when we see something that supports what we want to believe. Agreeing with us is the most popular persuasion technique today. We should be vigilant with those who agree with us a little too hard.
Critical thinking is about intellectual humility. So go and lead a humble life.