Scientific skepticism can sometimes be hard. It only takes a few seconds to make a bullshit pseudoscientific claim, but digging up all the scientific details to debunk it can take hours or even days. To streamline this process, as well as to provide a general introduction to the thinking behind scientific skepticism, here are four easy steps to critically review any questionable claim.
Can the idea or model even be meaningfully defined?
Perhaps surprisingly, many ideas out there are not even meaningfully defined. How can this be? Fundamentally, it boils down to the fact that some ideas almost completely lack intellectual content, but attempts to pretend it is of great substance. These are imposters of intellectual discourse that contaminate and pollute rather than inform and enlighten. For instance, postmodernism blends dense, convoluted and intellectually vacuous language with relativistic attacks against science by dismissing robust findings as merely “western”, “patriarchal” and “orthodox”, while advocating simplistic and faulty understanding of knowledge and the nature of reality.
Basically, some ideas are just so ludicrous and empty that they can be rejected at this stage already. If an idea, model or system of thought cannot be meaningfully defined, it is meaningless to go on. No point in spending time looking at evidence for ideas that cannot even be defined properly. Skeptical attention is better placed elsewhere. If the model is meaningfully defined, it is time to go on to the next step and check it for contradictions or inconsistencies.
Does the idea or model contain any contradictions or inconsistencies?
It is not yet time to look for evidence. First, additional internal investigation of the proposed idea needs to be carried out. This is because some models that can appear meaningful in many of its parts can contain contradictions or other kinds of inconsistencies. It might be possible to iron out some of these, but others might be lethal. This is because you can logically derive anything from a contradiction according to the principle of explosion and it is not really clear how a contradictory model could describe anything that exists in reality.
Is the idea or model supported by any evidence?
So the idea is meaningfully defined and does not seem to contain any obvious contradictions? Good. However, an idea should not be believed just because it is meaningfully defined and consistent. The claim that the U. S. President is an alien reptile is non-contradictory, but hardly a credible notion. Therefore, evidence needs to be presented in order for a questionable claim to be accepted as provisionally reasonable. So what is evidence? Can anything be evidence? Well, evidence is something that increases our confidence in an idea. One can start by assuming that the model is correct, and think about what one would expect given this model. If these expectations are observed, they constitute evidence for the model. The more substantial and precise the expectations are, the better the evidence they are if they are corroborated by empirical data.
The better the evidence, the more confidence we can have in an idea. As David Hume said in An Enquiry Concerning Human Understanding, “In our reasonings concerning matter of fact, there are all imaginable degrees of assurance, from the highest certainty to the lowest species of moral evidence. A wise man, therefore, proportions his belief to the evidence.”
Does the evidence favor it over alternative ideas or models?
Being supported by evidence is good, but sometimes it is not good enough. This is because there could be competing ideas or models that have even more evidence in their favor. Thus, it is often a good idea to explore other alternatives, and critically investigate the amount of evidence, if any, that supports them. Once a broad spectrum of alternative ideas or models have been identified and the amount of evidence in their respective favor have been established, it is possible to eliminate those that are largely unsupported by evidence and select the one that currently has the most evidence in its favor.
This is no means an exhaustive skeptical algorithm. For instance, it is often much more complicated to critically weigh different kinds of evidence against each other and sometimes the existing research is of too low quality to make an informed judgement besides tentative suspension of judgement. However, this list serves as a basic outline of useful ways to approach questionable claims.
Scientific skepticism in four simple steps:
(1) is the idea meaningfully defined?
(2) is the idea logically consistent?
(3) is there any evidence for the idea?
(4) is there more evidence for the idea than any competitor?
It is often much more complicated to evaluate complicated claims, read highly technical scientific papers and weigh the evidence for different ideas, but this provides a simple flow charts for introducing scientific skepticism.