Ad hominem index, revisited

The presence and frequency of ad hominem arguments in a policy debate is an indicator of a weak argument.

We don’t want to restrict the speech of others, but we have the right to choose what information we consume. And the aggregate effect of those choices has the potential change the calculus of polarization.

This is not an article about open source tax policy, but it is about openness and transparency in policy debate. I am revisiting an article I wrote nearly 15 years ago on June 30, 2009 on the original Econosseur blog. My article was entitled “On Economic Debate—the Ad Hominem Index”.¹ Given that we are entering the heavy season of the 2024 general US Presidential election, this article seems especially relevant.

My old article starts off by highlighting a characteristic of the Nobel Prize winning (1976) economist, Milton Friedman (1912-2006), as described by his longtime coauthor and collaborator, Anna Schwartz (1915-2012), in her June 2009 review of a biography of Milton Friedman.²

“For example, Friedman's style as a debater reveals an aspect of his personality. He was always courteous to his opponents in a debate, never attacked ad hominem. He concentrated on weaknesses of the opponent's arguments and invariably emerged as the victor in the debate.”

The term, “ad hominem”, is latin for “to the man” or “to the person”. An ad hominem argument is a well known logical fallacy in which a case is made using “an attack on the opponent’s character rather than the opponent’s argument.”³

My point in the original blog post was to highlight my admiration of policy debates and arguments that avoid ad hominem arguments. I then looked at an example of a long series of exchanges between two popular economist/bloggers of the time, Greg Mankiw and Paul Krugman (Nobel Prize in economics, 2008). I noted a general lack of ad hominem attacks in the arguments of one author in contrast to the other author’s near ubiquitous use of ad hominem attacks.

My thesis of the old article was that the presence and frequency of ad hominem arguments in a policy debate is an indicator of a weak argument. The ad hominem index was a conceptual proxy heat measure of the weakness of a debater’s position. Unfortunately, the logical fallacy of ad hominem arguments are believed to be particularly effective, even if the literature on this is inconclusive.⁴

I propose three approaches to sift through distracting ad hominem attacks to be able to better get to the core substance of arguments.

(1) Media should explicitly calculate an ad hominem index.

(2) Big tech companies should offer AI (artificial intelligence) ad hominem filters.

(3) Voters must choose to exclude ad hominem arguments.

One of my favorite characteristics of open source policy modeling is that the openness and transparency of the models renders them fundamentally apolitical. That is, a user might not agree with my previous policy positions, my training, or the organizations for which I have worked. But because all of my modeling assumptions are out in the open, an interested policy proponent has more of an incentive and requirement to comment on the assumptions of my model rather than any personal characteristics of mine. This is a much more productive scientific and democratic form of debate and collaboration.

What if our two presidential candidates used no ad hominem attacks? What if we never heard the phrases “crooked Joe Biden” or “loser Trump” in campaign events? The ad hominem attacks distract from the substance and nuance of the policy stances and characteristics the candidates support. Ad hominem attacks divert voter attention away from the policies.

Negative political attack ads and arguments are rightfully protected under the freedom of speech component of the First Amendment of the US Constitution, as long as they do not contain patently false statements or libel.⁵ If freedom requires minimal restriction on ad hominem arguments and negative attack ads, what can be done? I propose three approaches to sift through distracting ad hominem attacks to be able to better get to the core substance of policy arguments.

1. Media should explicitly calculate an ad hominem index for campaign speeches, political advertisements, articles, and political debates. I don’t know what the mathematical formula for this index should be. But it could include quantification of the number of unrelated personal attacks per substantial topic or policy area or the number of personal attacks per word. This index value could become viewed as a sufficient statistic for the soundness of an advocate’s arguments (low value ad hominem index value being associated with good arguments). Imagine if CNN and Fox News both posted independently calculated ad hominem index values for political candidates.

2. Big tech companies should offer AI (artificial intelligence) ad hominem filters for both written and video speech. These filters could be trained on previous year’s debates, ads, and articles with ad hominem arguments labeled by experts. As such, an AI ad hominem filter would depend on how it was trained. Because of this variance, it would be important for a competition of filters to exist. Versions of these AI filters already exist in OpenAI’s ChatGPT model.⁶

3. Voters must choose to exclude the ad hominem attacks of their candidates. This is the hardest requirement. The truth is that we humans love our biases to be confirmed by outside sources.⁷ This is why we tend to more happily tolerate ad hominem attacks from our preferred candidates and are more likely to condemn ad hominem attacks from our less preferred candidates. We must choose to exclude the ad hominem attacks of all candidates. This is a hard sell. But we need to opt in on the AI ad hominem filters (which don’t explicitly exist yet) and assess the ad hominem index values (which don’t exist yet) on the speeches, ads, articles, and debates we consume. At the very least, we can be individually more discerning as to which arguments are valid.

I am tired of polarization, demonizing of opponents, and negative campaigning on all sides of the political spectrum. I long for a day when candidates debate the costs and benefits and winners and losers of different policy options rather than attack their opponent’s person. How nice it would be for policy advocates to self impose logical consistency (the lack of logical fallacies) in their arguments.⁸

If our political system and candidates are currently in a bad equilibrium in which all sides have the incentive to use ad hominem arguments and negative attack ads, we the voters might be able to change their incentives by opting in to metrics and filters that restrict our access to these fallacious approaches. We don’t want to restrict the speech of others, but we have the right to choose what information we consume. And the aggregate effect of those choices has the potential change the calculus of polarization.

UPDATE (June 20): Hattip to Bob Ewing of Ewing School (those who know, know). He sent me this investment pitch video on WeFunder.com for a new group called AllSides Technologies, Inc. Among other things, AllSides says their BiasChecker AI product will be released soon. Their description is the following:

“The AllSides Bias Checker provides instant bias ratings and analysis for any news article. Since it is based on the AllSides patented bias system, it reflects the average judgment of all Americans, not just a panel of insiders or the musings of a biased AI system.”

1. I no longer own the Econosseur.com domain, so the original article has to be accessed through the Way Back Machine Internet Archive using this URL: https://web.archive.org/web/20160323115734/http://www.econosseur.com/2009/06/on-economic-debate--the-ad-hominem-index.html.

2. This passage comes from Anna Schwartz, “Milton Friedman: A Biography by Lanny Ebenstein”, Book review, Journal of Economic Literature, June 2009, pp. 495-496. Schwartz’s review of this particular Milton Friedman biography was pretty critical. The quote I selected from her review was a point about Friedman that was not included in the biography.

3. See Jeffrey Olen, Applying Ethics: A Text with Readings, Wadsworth Thompson Learning, 2002, p. 66. This is one of my favorite books on the subject of ethical debate.

4. Donald Green, “Do Negative Political Ads Work?” Scientific American, Sep. 2013 concludes that the empirical evidence for effectiveness of negative political ads is inconclusive. However, he notes that campaign consultants clearly must believe they are effective because they use them heavily. See also Richard R. Lau, Lee Sigelman, and Ivy Brown Rovner, “The Effects of Negative Political Campaigns: A Meta-analytical Reassessment,” Journal of Politics, 69:4, 2007, pp. 1176-1209.

5. In 2014, the US Supreme Court unanimously voted to remand the case Susan B. Anthony List v. Driehaus back to the Ohio federal courts, which voted to protect the political negative campaign ad (bilboard) speech of Susan B. Anthony List against a US Representative from the state, Steve Driehaus. See https://en.wikipedia.org/wiki/Susan_B._Anthony_List_v._Driehaus. In the State of Ohio Supreme Court decision, Judge Timothy Black said in his ruling, “The law steers far clear of requiring judicial determination of political ‘truth,’ and does so because of the serious dangers to democracy and the political process that would result from turning the courts into ‘truth squads’ with respect to core political speech on matters of public concern.” See “Renewed motion for summary judgement,” doc. 89, Jan. 25, 2013. “We do not want the government (i.e., the Ohio Elections Commission) deciding what is political truth—for fear that the government might persecute those who criticize it. Instead, in a democracy, the voters should decide…. Even false speech receives some constitutional protection.” See “List v. Ohio Elections Commission”, 45 F. Supp. 3d 765, 2014.

6. In his April 6, 2021 article, “Fantasy Intellectual Teams: version 2.0”, Arnold Kling highlights eight characteristics of high quality discourse. In his description of the “steel-manning” quality, he highlights the necessity for removing ad hominem arguments and attacks. In a Dember 15, 2023 article entitled, “More Essay-grader Results”, Kling uses ChatGPT’s essay grader functionality to evaluate a particular curriculum document. The grading output includes “engagement with opposing views”, “demonstration of open-mindedness”, “argumentation quality”, “avoidance of inflammatory rhetoric”,

7. See “Confirmation bias”, Wikipedia, accessed Jun. 9, 2024.

8. A great list of logical fallacies is in the book Jeffrey Olen, Applying Ethics: A Text with Readings, Wadsworth Thompson Learning, 2002, pp. 66-68. A great web reference is the site https://www.yourlogicalfallacyis.com/.