What is CT?

Definition
Simply put, critical thinking (CT) is figuring out how likely it is that a given fact claim is true.

To do this, you have to master concepts, skills, ethics, and impediments, but more on that in a bit.

Like reading or writing, CT is independent of any particular subject. You can apply CT to fact claims in any domain. You can teach CT in any subject.

CT must be learned
We aren’t born good critical thinkers, nor do we naturally turn into them. Like riding a bike or singing a song, to be good critical thinkers, we have to learn and practice critical thinking until it becomes second-nature.

Here are some reasons why CT doesn’t just come naturally:

Childhood credulity
We evolved to uncritically accept what adults tell us, and for good reason. When a parent tells a child that running into the street is dangerous, it’s good that the child believes it without testing it out. But the flip side is that children can also readily accept false information, leading to misinformed beliefs that may persist through adulthood. You can read more about childhood credulity here.

Common thinking errors
A large body of psychological and neuroscientific research has established that most of us are prone to a host of errors in logic, perception, estimation, and memory. All of these are barriers to critical thinking. You can read more about thinking errors here

Counterintuitive / Unintuitive concepts
Critical thinking relies on knowledge that took hundreds or even thousands of years of cumulative thought to develop, like math, the scientific method, and logic. Moreover, these concepts continue to evolve. This knowledge does not come to us naturally.

The elements of CT
Becoming a good critical thinker mastering concepts, skills, ethics, and impediments. Students can start this process in kindergarten and continue throughout their educational career. Basic, intermediate, and advanced examples of each category are given below.

Concepts
Basic: Facts and claims. First-hand and second-hand evidence.

Intermediate: The qualities of sound methods. Casual and scientific evidence.

Advanced: Prior plausibility of a fact claim. Probability of outcomes.

Skills
Basic: Using sound methods. Hypothesizing. Gathering evidence.

Intermediate: Devising sound methods. Evaluating evidence. Devising arguments.

Advanced: Calculating probabilities. Identifying thinking errors in arguments. Identifying the expert consensus.

Ethics
Basic: Valuing knowing the truth over winning an argument. Honesty.

Intermediate: Evaluating arguments on their merit, regardless of the motive behind them. Intellectual humility.

Advanced: Intellectual charity. Civil discourse.

Impediments
Basic: Arguments from memory. Arguments from authority.

Intermediate: Motivated reasoning. Arguments from ignorance.

Advanced: Implicit bias. Insufficient or skewed access to information.

The language of CT
Like many subjects such as geometry or physics, CT uses precise terms like “indirect evidence”, “fact”, and “confirmation bias” to describe things. By establishing a common language of CT, the knowledge, skills, and ethics it requires can be transferred from one subject to another and from one context to another. Click here to learn more about the language of CT.