"Pete is Pete": what tautology can tell us about a person’s character

The research on the interpretation of tautologies was supported by the Russian Science Foundation (project No 19-78-10048). The research findings are published in the scientific journal Journal of Pragmatics.

In everyday discourse, we often use tautologies, being sure that our message is clear. Thus, when a person exhibits his or her typical behaviour pattern, like being late, people can easily describe this using a tautological expression: ‘No wonder! Pete is Pete.’ And as the linguists have revealed, even a passerby, not knowing who Pete is, would arrive at the same interpretation effortlessly. In other words, being presented with the fact that Pete has missed his plane and the tautology Pete is Pete will suffice to conclude that Pete is habitually late.

Nonetheless, linguists Elena Vilinbakhova (St Petersburg University), Victoria Escandell-Vidal (Complutense University of Madrid) and Natalia Zevakhina (Higher School of Economics, Moscow) found out that the felicitous use and interpretation of tautologies has its own requirements and constraints. To verify their preliminary findings, the researchers conducted an experimental study. The participants in the study were asked to select an interpretation of tautologies for different situations. For example, they were given a tautology "Mary is Mary" and a description of the fact that Mary has been delayed at work, suggesting that Mary often has to stay late to work. The experiment results helped the researchers to formulate two main principles of the interpretation of tautologies.

On the one hand, shared knowledge is not a necessary requirement for the felicitous use of tautologies. Thanks to the universal human ability of the so-called abductive reasoning — the search of explanations for the given facts — lack of previous knowledge can be repaired by accommodating new assumptions or compensated by providing additional explicit content. Thus, the hearer will be able to infer the appropriate conclusion. This emphasises the fact that the tautology can be self-sufficient without additional contextual cues.

Elena Vilinbakhova, Principal Investigator of the project, Associate Professor in the Department of General Linguistics at St Petersburg University, explains that the tautology conveys the message by bringing to the foreground a shared assumption without mentioning it explicitly. However, this is not the only possibility. The tautology is especially interesting when there is no shared knowledge or additional interpretive cues in the context; yet, the hearer can build an acceptable interpretation for the tautology.

The study revealed that people can successfully interpret the tautology without previously shared knowledge, even if the individual that is being referred to in the tautology is a fictional character or completely unknown person.

Elena Vilinbakhova, Principal Investigator of the project and Associate Professor in the Department of General Linguistics at St Petersburg University

‘Relying on the conversation flow, hearers can infer their conclusions about what the speaker implies. This shows that the hearer’s previous knowledge about the referent is not always necessary for an adequate interpretation,’ said Elena Vilinbakhova.

Moreover, shared knowledge is not a sufficient condition either. Only permanent attributes can be evoked by a tautology. There are additional constraints on the evoked knowledge and difficulties in interpretation related to episodic or transitory states of the referent — for instance, associated with weather, mood, health, and other non-permanent characteristics.

According to Elena Vilinbakhova, transitory states were systematically rejected by the study participants even if they constituted shared knowledge and were supported by the context. Only a tautology interpreted as a permanent property of an individual under discussion will be accepted by the interlocutors.

The conducted experimental study enables us to assert that shared knowledge does not guarantee the recoverability of a meaningful interpretation for a tautology.

Elena Vilinbakhova, Associate Professor in the Department of General Linguistics at St Petersburg University

‘For a tautology like "Pete is Pete", the research participants systematically rejected the transitory state interpretations, such as: "Pete is busy now" or "Pete is sick". Only permanent, classificatory attributes were selected as the intended message conveyed by the tautology, for instance: "Pete is constantly playing sports" or "Pete is smart",’ shared Elena Vilinbakhova.

The participants in the experimental study were English native speakers. Hence, the obtained results show primarily how the tautologies work in English. Their validity for other languages still needs to be examined. Nonetheless, the authors believe that the research can be replicated for other languages and plan further study. The research findings can be relevant for automatic text processing when solving problems such as Recognising Textual Entailment with logical inference from a text fragment, as well as in the field of general argumentation theory.