Since I wrote this letter to the Irish Times earlier this week, I’ve been thinking about what critical thinking actually is.
Basically, I believe that all of what we call critical thinking is recall; it’s not some mysterious process somehow separated from more ‘normal’ mental processes like remembering who won the FA cup in 1973 or what the longest river in the world is or what the atomic weight of Neon is.
So here’s what I think: when somebody is thinking critically, they are simply accessing (what they perceive to be) relevant knowledge stored in their long term memory, and they are using to it to bolster their original argument.
For example, many of my students, when encountering anomalies in experimental data, will say things like “the rise in flowrate was unexpected and was probably due to experimental error”. This is an example of student who is not thinking critically but it’s not because they can’t think critically; it’s because they are either intellectually lazy or else they simply have no idea what factors might cause the flowrate to rise, i.e., they lack relevant knowledge and they resort to writing down something – anything – that seems plausible. But having submitted their lab report and gained some feedback, this student will learn that in future they shouldn’t just ‘throw out’ statements that cannot be justified in some way, and hopefully their next report will be better. This is an example, I suppose, of “teaching critical thinking” but it’s done in a context that is tangible for the student and targeted at scenarios that they are likely to encounter in their discipline. This should be, and hopefully is, a normal part of university education.
A better student might say something like: “the rise in flowrate was probably due to a rise in pressure”. This student is connecting an experimental observation to knowledge that he or she has stored in their long term memory, namely that a rise in pressure will cause an increase in the flowrate. But an even better student might say something like: “the rise in flowrate may have been due to a sudden rise in pressure as it was observed during the experiment that the pressure tended to fluctuate and it was difficult to control using the manual approach that we employed”. This student has high expectations and is determined to provide as complete an explanation as possible. But his explanation is built, fundamentally, around recall; both accurate recall of what happened in the experiment itself and recall of relevant theory from long term memory.
So I think critical thinking emerges when a person has two attributes: (i) the right mindset, i.e., a desire or need, either innate or acquired though feedback, to base their conclusions on the justifiable rather than the plausible; (ii) having relevant and accessible knowledge stored in long term memory.
But what do we mean by “accessible” knowledge? I think the highest-achieving students have automatic recall of relevant facts. They will have achieved this ‘automaticity’ through effective and regular study/practice and not necessarily through a conscious effort to ‘learn off’ facts. If you like, key knowledge is firmly embedded in their long term memory and in a way that makes it rapidly accessible. Observations or statements or claims trigger a ‘visit’ to long-term memory where easily-accessible and relevant knowledge is retrieved. This combination of observation and accessible knowledge creates the process that we call critical thinking.
An academically weaker student, or a student who might not have studied so hard, or who might not have paid enough attention during the laboratory session, won’t have this automatic recall even if relevant facts or part-facts can be ‘dragged out’ of them following some prompting from the lecturer. This will make them appear to lack critical thinking skills when what they really lack is readily-accessible relevant knowledge.