1 What Are Enthymemes, When Do We Use Them, and Why Should Tab Judges Care?

Most national circuit judges in high school LD would describe their baseline judging paradigm or philosophy as tabula rasa or “tab”/“tabs” for short [1]. Tabula rasa means “blank slate.” The idea is roughly that a judge’s mind should be a blank slate entering the debate. Only the arguments and evidence in the round –not the judge’s prior beliefs – should play a role in the decision. There are a number of different glosses to put on the concept, but which definition is most precise and which version most justifiable are questions for another day [2].

The problem this post presents is how a tab judge ought to deal with enthymemes. An enthymeme is a rhetorical device, often attributed to Aristotle, where the speaker omits a step in reasoning. You may have learned this term in a high school English course in rhetoric. As a quick refresher, take the following syllogism:

            Premise 1 (P1): If you smell smoke, there is a fire.

            Premise 2 (P2): If there is a fire, call the fire department.

            Conclusion (C): If you smell smoke, call the fire department.

Reasoning enthymemetically, one might say instead,

            P1: If you smell smoke, there is a fire.

            C: If you smell smoke, call the fire department. [3]

While not logically valid, the inference to P1 to C is a fine argument in most contexts. This is because P2, “If there is a fire, call the fire department,” is assumed by the speaker and the audience. In fact, enthymeme literally means “in the mind” [4]. While unstated, P2 is “in the mind” of the speaker and the audience such that the argument makes sense without it.

At this point, the tension should be clear: How can a judge who claims to be a blank slate assume a premise in an argument? Isn’t that reading something into the speech? [5] Isn’t that intervention? Yet we allow enthymemes in debate all the time.

On this website, I have argued that internal links to fairness are unnecessary, and Adam Tomasi wrote a similar piece about late rebuttal extensions. Both, we said, should be assumed by debaters and judges. In effect, we were arguing for greater use and acceptance of enthymemes. On the other side, Marshall Thompson forcefully argued against an application of enthymemes to spikes. He criticized preemptive arguments for lacking a clear application to any negative strategy before the 1AR (even when the implied premise is fairly obvious). Thus, he defended the contextual model of spikes, one where negatives have a new opportunity to address spikes in the 2NR after the implied premise (from the 1AC) is explicitly stated (in the 1AR). He can be read as fixing a problem with enthymemes.

A particularly high-profile (see here, here and here) example of argument over enthymemes was the controversy about whether “racism is bad” need be explicitly stated in a debate round. It’s no surprise that some of the theorists opposing this use of enthymemetic reasoning view themselves as tabula rasa, non-interventionist judges. We know from the writing in favor of the enthymeme that allowing normative assumptions about marginalization can help foster a more inclusive community. Unfortunately, none of these authors provide clear criteria for assessing more standard cases like the ones cited above.

If one still doubts the use of enthymemes in common debates, consider the following examples (the implied premise is italicized in parentheses):

            P1: I have won my case.

            (P2: If I have won my case, vote for me.)

            C: Vote for me.

Here’s another, less obvious assumption:

            P1: Act-consequentialism is the correct moral theory.

            P2: The plan causes extinction.

            (P3: Something that causes extinction is bad if act-consequentialism is the correct moral theory.)

            C: The plan is bad.

And here’s an example from the 2016 January-February topic:

            P1: Substitution effect: the plan causes handgun owners to buy long-guns such as rifles and shotguns.

            (P2: If handgun owners buy long-guns, overall gun violence increases)

            (P3: If the plan increases overall gun violence, I’ve turned the advantage)

            C: I’ve turned the advantage.

When the judge has read the relevant topic literature and judged dozens and dozens of debates on a topic, a term like “substitution effect” can mean a lot more than the two words suggest. When I heard “substitution effect,” I was already thinking P1, P2, P3, and C without any additional prompting. When I mentally fill in the gaps like this, am I intervening?

This uncertainty is a problem in a number of circumstances where reasonable judges’ opinions may differ:

  • Debater says “Substitution effect turns the case” but omits an explanation of the substitution effect and why it turns case.
  • Debater says “Prefer my framework because it’s more specific to government obligations” but omits a justification for why frameworks that are more specific to government obligations are preferable.
  • Debater says “My topicality definition increases clash and depth on the resolution, which is more educational” but omits the conclusion “vote on the more educational topicality definition.”
  • Debater says “My opponent’s rhetoric is a microaggression, so vote for me” but omits premises inferring the need for the ballot from the utterance of a microaggression.
  • Debater says “Fairness is a voter” but omits a clear conclusion. Debater means to conclude “Drop/reject the debater if I win theory” but judge interprets “Drop/reject the argument if I win theory.”

Most of these are more significant cases where enthymemes can create problems. Of course, there are more mundane occasions when we could say debaters employ enthymemetic reasoning. Nebel wrote here that “[b]oth sides must, by logical necessity, appeal to assumptions for which no argument is given” (para. 8). This seems plausible because of time constraints (unless all arguments in a speech relied on circular reasoning). And if it’s the case, then all arguments involve enthymemetic reasoning to a certain extent. I’m more concerned with when these assumptions are significant and can determine the outcome of a debate, but it’s worth noting that the arguments below could have greater import.

I’m going to divide debates involving enthymemes into two types: one where the respondent contests the implied premise and another where the respondent does not. Both are tricky for judges.

2 Contested Assumptions in Enthymemes

If the respondent contests the implied premise, a problem arises. Because there was no statement of the premise, let alone a warrant for it, what is the enthymeme-user to do? If there is no justification for education as a theory or topicality impact when theory or topicality is first read, is “no impact to education” a knockdown response? Perhaps merely pointing out the assumed premise is insufficient, but refuting it seems like enough. Suppose the respondent not only argues that the education impact is implied, but education is also worthless or even harmful! These arguments are likely terrible, but some argument is better than no argument on the issue (traditional debate wisdom would have us believe).

The tab judge could say that the enthymeme-user cannot provide new justifications for the implied premise in the subsequent speech. First of all, there is only one constructive in Lincoln-Douglas debate (so perhaps this problem is less relevant in other formats). Second of all, allowing a new defense of assumed premises in a subsequent speech could create perverse incentives to ‘sandbag’ the best arguments for later in the debate, which prioritizes argument avoidance over engagement.

This conclusion is unfortunate, however, in contexts where the implied premise is exceedingly obvious. A typical affirmative might read a framework and a plan but fail to explain how the advantage impacts link to the framework or why winning the case is sufficient for the judge to vote aff. Imagine a negative speech that points out the plethora of these reasonable and accepted enthymemes employed by the aff. Such a world would create a really poor form of debate. Any 1AR attempt to justify the implied premises or conclusions could be construed as providing new constructive arguments in violation of the time-honored debate rule against new arguments in rebuttals.

A different 1AR tack is to make a theory argument that some implied premises should be allowed. This route requires no new constructive arguments in the 1AR. The aff could say the assumption that a case in favor of the resolution implies an aff ballot is perfectly reasonable and avoids drawing an arbitrary line by arguing that assumptions of type X are reasonable and others are not. The problem, however, is that such an interpretation seems at odds with tab judging. The aff is arguing that the debaters and the judge should make assumptions of type X, explicitly invoking a degree of judge intervention. In the particular debate in which the theory argument is made, no intervention is necessary, but a hypothetical debate abiding by the aff interpretation would be one in which judges do make assumptions of type X. And by stipulation, tab judging precludes any such insertion by the judge.

3 Conceded Assumptions in Enthymemes

An especially tricky case arises when the enthymeme is accepted by the opponent. I can think of a couple of options for a tab judge in this scenario:

  • the implied premise or conclusion is conceded, so the judge should treat the argument as true
  • the implied premise or conclusion was never explicitly argued, so the judge should treat the argument as false
  • the judge should treat the argument as just as true as her own intuitions suggest

On face, option (2) seems more interventionist than (1) and (3) given the backdrop of LD judging norms where dropped arguments are treated as true. Of course in this context, there is no dropped argument. There is a dropped assumption or hidden premise. So perhaps the norm should not apply. Option (3) seems obviously interventionist because it invokes the judge’s own judgment about the strength of an implied premise. But even option (1) is interventionist because it requires the judge supply the missing premise in the first place. Cossette (2015) provides an example for why this would subvert the very idea of tab judging:

“You must explain to a tabula rasa judge why certain issues in the debate are important…You cannot just say, ‘They dropped inherency, which is one of the stock issues, so they lose automatically’” (p. 149)

An assumption that inherency is a voting issue seems especially interventionist because on some models of debate, inherency is irrelevant. So supplying the inherency-as-a-voter premise would require a robust assumption on the part of the judge [6]. But when someone says “X is a voting issue” without further justification, the knee-jerk tab reaction is likely to accept it as true until disproven. Characterized in this light, (1) might be a problem.

Yet in other contexts, where the judge makes a very basic assumption, (1) seems much better than (2). Take the example above where a debater argues “P1: I have won my case. / C: Vote for me.” without “P2: If I have won my case, vote for me.” All else equal, winning one’s case should result in a victory on almost any model of debate, so this seems less interventionist.

So what do we do? All of (1), (2), and (3) can seem interventionist to varying degrees depending on context. One idea is that a judge should pick (1) or (2) up front so that debaters can at least predict how the judge might be interventionist in evaluating enthymemes. This is a weak solution nonetheless because although more predictable, it still allows a great deal of intervention.

Second, adopting (1) or (2) wholesale just moves the bump under the rug. The judge still must determine when a premise or conclusion is implied. A judge who thinks that “voter for fairness” on a theory argument always means “drop the debater” will not see the sentence as enthymemetic. A judge who thinks it could mean “drop the debater” or “drop the argument” will.

I believe this is true of most debates involving enthymemes. To identify a missing premise, a judge will inevitably use his or her background, experience, and particular perspective in judging debate rounds. How could we not?

If this is true, then intervention of the kind explicitly called for by (3) is unavoidable. When enthymemetic reasoning is involved, judges will discount arguments that they view as assumptive and allow arguments that they do not identify as assumptive regardless of the arguments of debaters (because there are none). (3) just requires that judges do this in a more specific way – assigning a particular level of credence in a hidden assumption.

Rather than totally allow or totally bar an enthymemetic argument, a judge should believe it to a certain degree. A reasonable assumption might be a well-known premise about U.S. foreign policy or a historical fact. A beyond-reasonable assumption might be an implication about what a judge should do with a won “RVI” argument (it’s definitional!). An unreasonable assumption might be a warrant for why inherency is a voting issue (above). The degree to which an assumption is reasonable will be decided by the judge and correspondingly increase or decrease the overall strength of the argument.


Enthymemes are sites of failure for tabula rasa judging – some intervention must take place because of incomplete argumentation, so what is a judge to do? I argued that when assumptions are contested, the burden falls on the debater making the assumption to justify why such an assumption is reasonable and should be allowed. When assumptions are uncontested, judges must use their own background experience to decide the strength of the assumption. Such a practice is inevitable and can produce better results than a one-size-fits-all rule of thumb.

End Notes

[1] I say this despite the recent surge in kritik and identity politics arguments in rounds and online that urge judges to deviate from the tabula rasa paradigm. First, these arguments don’t displace tabula rasa; they merely modify it. E.g. the call for judges to reject implicitly racist rhetoric can be read as an exception: “Be a blank slate except when debaters use implicitly racist rhetoric; then drop them.” Second, the prevalence of “roles of the ballot,” kritiks, and identity politics literature is an argumentative trend like any other. This post is about what I view as an enduring and general LD judging practice.

[2] That said, it’s easy to see why the tab approach is readily accepted by contest debate judges. Other paradigmatic moves are casted as “interventionist,” and after all, “the purpose of debate is not primarily to evaluate policy or to find truth.” (Rowland, 1982). In addition, “[a]ll judges work to be tabula rasa to some degree, striving to make their decisions based on the arguments offered by the debaters in the debate round, and not based on their predispositions about the topic and the materials presented” (Freeley & Steinberg, 2009, p. 325). The difference in degree might lead us to a more fine-grained take on the varieties of tabula rasa judging. I should also note but will not explore that the idea of judge as tabula rasa is a long-standing idea in American jurisprudence as well: “The adversary system is founded upon the idea of the judge as tabula rasa” (Weinstein, 1995, p. 108)

[3] I owe this particularly clear example to Professor Stephen O’Leary at USC.

[4] Heinrichs (2013).

[5] I came across this pretty cool passage in a discussion of the philosophy of art, which explains how enthymeme invites active participation by the audience, which the tabula rasa perspective explicitly disavows:

“It involves a complex interrelation between the framer and the reader of the enthymeme. The latter must himself fill the gap deliberately left open by the former: he must supply what is missing and draw his own conclusions (“his own conclusions” are those “anyone” would draw). He is not, as a passive auditor, told what to put there; he must find that out and put it there himself, participating in the common procedure of reason…In a small way, the audience for the enthymeme acts as all readers ideally should, participating in a process rather than just being encoded with information as a tabula rasa” (Danto, 1981, p. 170).

[6] Nails (2015) notes in a related discussion of dropped arguments generally that the idea that a conceded argument should be granted 100% credence is itself an assumption on behalf of the judge (para. 13). He takes for granted that this is a problem for tabula rasa, which must be “recalibrated.” But a tab judge could think that the dropped = 100% true mantra is itself interventionist. Why should a judge make that assumption, akin to (1) above, instead of assumption (2) or (3)?

Note that my final conclusion does not go as far as Nails. There could be reasons for judges to supply their own reasoning in cases of dropped enthymemes but not dropped arguments or vice versa.

Non-Blog References

Cossette, N.A. (2015). The art of debate. Retrieved from https://books.google.com/books?id=9uaJCgAAQBAJ

Danto, A.C. (1981). The transfiguration of the commonplace: a philosophy of art. Cambridge: Harvard UP.

Freeley, A.J. and Steinberg, D.L. (2009). Argumentation and debate. Boston: Wadsworth Cengage Learning.

Heinrichs, J. (2013). Thank you for arguing: What Aristotle, Lincoln, and Homer Simpson can teach us about the art of persuasion. New York: Three Rivers Press

Rowland, R.C. (1982). Standards for paradigm evaluation. JAFA l8 (Winter, 1982): 133-140.

Weinstein, J.B. (1995). Individual justice in mass tort litigation: the effect of class actions, consolidations, and other multiparty devices. Evanston: Northwestern UP.



Bob Overing | Co-Director

Bob is a co-director of Premier, coach for Walt Whitman HS, and current Yale Law School student. As a senior in high school, he was ranked #1, earned 11 bids and took 2nd at TOC. In college, he cleared at CEDA and qualified to the NDT. His students have earned 80 career bids, reached TOC finals, and won many championships.