Vast changes have occurred in the past 25 years with respect to how we access information. In short, the internet has made it much easier. With that said, all that is available isn’t necessarily true, so we must think critically about the information we obtain if we care about our decisions. One important way in which we can evaluate such information, and conduct critical thinking, is through both identifying the source of the information and knowing about the credibility of such sources. From my work in the area of critical thinking (Dwyer, 2017), it seems that all sources of information boil down to five separate areas: (1) personal experience and/or anecdotal evidence; (2) common belief; (3) research; (4) expert opinion; (5) and statistics. If you’ve come across any other distinct categories, please drop me a line and let me know!
1. Personal experience and/or Anecdotal evidence
Experience is a great educator. When you boil it all down, learning, be it in the classroom or otherwise, is experience, the experience of engaging with information and storing it for later recall and application. However, relying on experience in situations wherein critical thinking is necessary would be a bad move. The problem with personal experience is that all it amounts to is anecdotal evidence, essentially a story. These stories can be very powerful in persuading people of our points of view, but they are a weak source from which to base an argument since they are not necessarily reliable or generalizable. A sample size of one cannot be generalized to the population at large because everyone has different experiences. If every person is special and unique, then why should any one person’s opinions and experiences be used as an example for others?
2. Common Belief
Common beliefs are ideas and concepts that we hear on a regular basis. They might refer to concepts the wider population holds true (without much consideration) or perhaps an old adage your mother used to repeat to you in childhood. The problem with common beliefs is that they’re not always correct. You may have heard the common adage that "opposites attract" but research suggests that we tend to like people who are similar to us and dislike people who are different. So, we can see here that scientific research findings are sometimes at odds with common beliefs. Likewise, common beliefs can be at odds with one another. For example, in this case, "birds of a feather flock together," is a common belief that actually is supported by research, and which directly contradicts the common saying above. Nevertheless, why not find a more credible source?
3. Research
Evidence-based research is the gold standard of credibility. When we use it as the basis for our decisions, we are using something that is not based on feelings, beliefs, or biases, but are dealing with objectivity. This does not necessarily mean that all research is of adequate or even good quality. When evaluating research, you must ask yourself whether a study was limited in some respect; for example, the design, sample assessed, measures used, or even the conclusions drawn. For example, in my book I use a fictional study wherein it was found that dogs enhance their owners’ well-being. This prompted a series of questions, including, "Were dog owners compared with people who do not have dogs on mental well-being?" Alternatively, it may be the case that dog owners were already scoring high on mental wellbeing, prior to owning dogs. Maybe that’s why they decided to get a dog in the first place. We must ask if this is an issue of cause or correlation. Could this hypothetical finding regarding high mental wellbeing stem from something other than owning a dog? Maybe it’s one’s caring nature and nurturing emotions that led them to get a dog that impacts their well-being? Still, the nature of research is that it's based on credibility. Numerous studies are conducted on the same concepts. Studies are replicated to assess the credibility and generalizability of findings. Thus, if you question the credibility of one study, see what other studies on the same topic say. Evaluate their methods and conclusions. Of course, no study is perfect, but if a large body of research indicates the "truth" of a certain phenomenon, it would be reasonable to incorporate these findings into your decision-making. However, if you find yourself siding with an idea that’s only supported by one study or suspect methodology, you may want to reconsider your stance.
4. Expert Opinion
If an expert with relevant qualifications in a particular field tells us something, we should be inclined to believe them. Many might be surprised by this recommendation because it seems like blind belief in authority, but there’s actually much more to consider. Expert opinions are a strong source of information because experts have to maintain their reputation in order to continue being seen as experts. Generally, the opinions expressed by true experts develop based on research findings. Expert opinions may differ from others in their field, but that’s okay. Debate is part of the scientific process. Likewise, expert disagreement may be due to different research perspectives. For example, a social psychologist may focus on the ‘nurture’ influences of aggression, whereas a neurobiologist may focus on the ‘nature’ aspect. Both will identify different contributors to aggression, but are also both likely to acknowledge the existence of each other’s perspectives. That’s what credible researchers do. However, some ‘researchers’ may not practice such intellectual humility or even have credibility. It’s one thing for me to present information on this platform regarding critical thinking and psychology—given that they are my areas of research—but it’s another for me to tell you about quantum mechanics. Unfortunately, some people take the platforms that they are provided and exploit them to spread what they believe, regardless of whether or not it’s misinformed. Overall, expert opinion is strong in credibility; however, it is up to that expert’s audience to evaluate the credibility of the ‘expertise’.
5. Statistics
Statistics are one type of output we get from doing research. The type of statistics reported often tell us something about the type and quality of the research. Statistics are another arena in which causation and correlation must be carefully considered. Researchers know a wide array of statistical typologies, all of which are chosen based on the research question and design. We should ask, "What is the purpose of this statistic? What is the goal of reporting it?" Every statistic is simply a number. This is actually what makes it such a strong form of evidence, it is objective. However, the manner in which that statistic is interpreted and presented is equally important with respect to determining credibility.
Discussion
Overall, a pattern emerges across these five informational sources. No source of evidence is perfect. If we care about the decision with which we’re faced, we will engage research, expert opinion, and statistics with care, ensuring consistency across the body of research in that field. Personal experience and common belief tend to be less helpful because they have no grounding in an evidence-based approach. In many cases, there may be research that either debunks such beliefs or maybe even supports them, but why bother with the middle man? Critical thinking takes time, so why spend more than necessary in humoring information that lacks a basis in evidence? Go straight for a source derived from research and use your valuable time well.