Cherry Picking

An informal fallacy where selected evidence is presented that supports the position of the argument, while contrary evidence is withheld. This is done in an attempt to make the argument more persuasive to an audience. Moreover, the greater the volume or strength of the evidence withheld dictates how fallacious the argument is. Regardless, if one engages in cherry picking of any degree, the argument is rendered bad as an incomplete world-view has been presented, which doesn't permit an accurate conclusion to be reached.

Logical Form

The current evidence available is either A or B.

  • Evidence A supports the Person 1's argument.

  • Evidence B supports Person 2's counterargument.

  • Thus, Person 1 only presents evidence A.

Cherry Picking.png

Examples

The usual procedure for this section is to fabricate fictitious scenarios to illustrate how the fallacy occurs or may be observed in everyday life. However, given my history with pseudoscience, I thought that it would be interesting if I were to re-evaluate some of the fallacious arguments that I used, admittedly, on more than one occasion, to argue my (wrong) position. Examples 1 and 2 are both arguments that I have used in the past to argue my pseudoscientific positions.

The following abbreviations are used in the examples below:

PN = The Nth premise for N = 1,2,3,…. (e.g., P1 is the first premise, P2 is the second premise, etc.)

C = Conclusion

1)

P1: Studies [1], [2], and [3] all demonstrate injurious effects as a result of consuming GMO foods.

C: Therefore, GMO foods are not safe for consumption.

Explanation: As with most studies supporting a fringe view, there are methodological issues with both [1] and [2], which has subsequently lead to them being dismissed by the scientific community as reaching unsupported conclusions (i.e., it's bad science and the results cannot be trusted). [1] was subtracted due to this, while [2] is published in a fringe journal that is known for lax standards in publication. Now, the source of the journal alone is not enough to discredit it (if we took this route, we would be committing what is known as the genetic fallacy), but it does help to craft an overall picture of credibility for the study. In other words, we should approach the results of this study with a high degree of skepticism.


Again, the conclusions reached by the study have not been dismissed because of the journal it was published in, but due to methodological issues that have lead the community to distrust the results. In particular, the Authors of this paper didn't include any rigorous statistical analysis when this is standard protocol for a study with a large number of parameters. Without including this, it is impossible to know for sure whether or not an observed result was due simply to chance or not.

[3] is just a correlation analysis. That is, the authors looked at glyphosate application data and how it related to epidemiological data for 22 different chronic diseases. While they indeed found strong correlations, none of this necessarily implies causation [4]. At the end of the study, the Authors conclude with “The significance and strength of the correlations show that the effects of glyphosate and GE crops on human health should be further investigated.” I concur, while a correlation analysis is interesting, this doesn't mean that glyphosate causes these diseases. That said, an amateur scientist (such as myself before receiving further training) or the general public, won't have the training necessary to fully understand that this study hasn't demonstrated that glyphosate causes these 22 different diseases. Unfortunately, this lack of understanding can then lead to abuse.


Last, this paper was also published in the same fringe journal as [2], which should trigger some red flags for us to rigorously investigate the statistical analysis that was done and make sure that there were no methodological errors. Why? Based off this journal's history of publishing anti-GMO studies that are methodologically flawed, it is prudent to approach this study with a healthy amount of skepticism and confirm that the science contained within is sound.


While I have provided multiple studies here, after further evaluation, it becomes clear that I have selected studies that are methodologically flawed or don't actually support my argument. Moreover, [1] is a retracted study and shouldn't be included in the argument at all as it fails to contribute to the truth of the premise. What is more, all of the studies presented are fringe cases when compared to the full body of evidence (i.e., I cherry-picked) [5]. As with all of science, while individual studies are indeed important, the full body of evidence is what's most important when trying to find truth.

2)

P1: Vaccines contain the preservative thimerosal, a mercury preservative, which can cause autism as demonstrated in [6].

C: Ergo, vaccines should be avoided as they can cause autism.


Explanation: Here, I am clearly cherry picking as I've only including one paper and when compared to the full body of evidence, thimerosal-containing vaccines don't cause autism [7]. Furthermore, this paper engages in a fair amount of speculation and isn't actually conducting an experiment, statistical analysis, etc. in order to better understand a possible mechanism between mercury exposure and autism. The entire paper is referencing other studies and frequently uses words such as “maybe, possibly, potentially, etc.” throughout. Overall, the paper doesn't say much other than “more studies are needed,” which the untrained eye would probably miss and mistake this paper as presenting conclusive evidence that mercury and/or thimerosal in vaccines are linked to autism.

Candidly, I would often use many different studies in my arguments surrounding vaccine safety. However, for didactic purposes, I thought it would be appropriate to demonstrate true cherry picking where I am only using one study to support my position. Reflecting on the studies that I used in the past, I can assure you that all of them have their flaws or weren't saying what I thought they were saying.

3) President Trump recently made the following statement in regards to the California wildfires and climate change [8]:

  • “Maybe it contributes a little bit. The big problem we have is management.”


Here, the argument being made is a bit muddled as is usual for Trump, but here is my interpretation:

P1: The primary cause of these wildfires is poor management of the forests, not global warming.

C: Therefore, we should focus on better forest management if we want to solve this problem.


Explanation: You might argue that Trump never said that global warming didn't contribute at all, which is true, he at least acknowledged that it may play a small role. But, given his past statements on global warming (e.g., “global warming is a Chinese hoax”), he is clearly attempting to down play it to a degree where some of his audience will think that global warming is nothing to be concerned about. This is why I have chosen to not be more charitable with my interpretation. 

It is true that forest management is important when it comes to the prevention of wildfires. It is also important to note that a larger population of people living in forested areas is going to play a role as well. That said, what is more, the science indicates that events of this nature will be exacerbated by climate change [9,10]. Now, to what degree each of these contributes is debatable. However, to diminish global warming's role to the point of dismissal in this unprecedented event (the past few years have produced the worst wildfires in California's history) is prevarication. Absolutely global warming is making these wildfires worse and, based off of current trends as well as the science, will most probably intensify in the future. Trump is cherry-picking from the body of evidence surrounding forest fires to support his argument that mismanagement is what lead to California's fires.


Conclusion

As is always the case, if you find yourself confronted with this fallacy in everyday discourse, it is important to remember that it renders the argument bad and should be rejected. What is more, if you find yourself using this fallacy within one of your own arguments, as an individual who ascribes to the philosophy of Critical Thinking, you must replace it with a good argument.

References

[1] Seralini, Gilles-Eric, et al. Long term study of a Roundup herbicide and a Roundup-tolerant genetically modified maize. Food and Chemical Toxicology (2012); Volume 50, Issue 11: 4221-4231.

[2] Carman, Judy A., et. al. A long-term toxicology study on pigs fed a combined genetically modified (GM) soy and GM maize diet. Journal of Organic Systems (2013); Volume 8, Issue 1: 38-54.

[3] Swanson, Nancy L., et. al. Genetically engineered crops, glyphosate and the deterioration of health in the United States. Journal of Organic Systems (2014); Volume 9, Issue 2: 6-37.

[4] Correlation Analysis – Market Research.

[5] National Academies of Sciences, Engineering, and Medicine. 2016. Genetically Engineered Crops: Experiences and Prospects. Washington, DC: The National Academies Press.

[6] Mutter, Joachim, et. al. Mercury and autism: Accelerating Evidence? Neuroendocrinology Letters (2005); Volume 26, Issue 5: 439-446.

[7] Centers for Disease Control and Prevention. Frequently Asked Questions about Thimerosal.

[8] Guardian Staff: “Trump blames wildfires on forest mismanagement again.” The Guardian (2018).

[9] Ebbs, Stefanie. “Undeniable link to climate change in California's fire season, expert says.” Abc News (2018).

[10] Harvey, Chelsea. “Here's what we know about wildfires and climate change.” Scientific American (2017).