Hi!

I'm a psycholinguist interested in natural language meaning, its acquisition, and how it interfaces with non-linguistic conceptual systems.

Lately, I’ve been focusing on the mental representations that serve as the meanings of quantificational expressions like each, every, and most. What are the formal properties of those representations? When do children have access to them? And how do learners figure out how to pair them with the right pronunciations? To get at these questions, I’ve used a range of methods including behavioral experiments with adults and children, habituation experiments with infants, psychophysical modeling, corpus analysis, and good old linguistic intuitions.

I'm currently a MindCORE Postdoctoral Research Fellow at the University of Pennsylvania, where I'm working with John Trueswell, Anna Papafragou, and Florian Schwarz. I earned my PhD in Linguistics in 2021 from the University of Maryland, where I was part of the Maryland Language Science Center. My dissertation -- The Psycho-logic of Universal Quantifiers -- was advised by Jeff Lidz and Paul Pietroski. Before that, I studied Cognitive Science at Johns Hopkins and managed Justin Halberda's Vision and Cognition Lab.

Research Projects

Universal Quantifiers:

A sentence like every circle is blue could be mentally represented as (i) a relation between two independent groups (the circles are among the blue things), (ii) a non-relational description of how the predicate applies to the members of one group ("is blue" applies exhaustively to the circles), or (iii) in a completely first-order way that implicates no groups at all (each thing that’s a circle is blue). Logically, these descriptions are equivalent. But psychologically, they correspond to distinct hypotheses about speakers’ mental lives. To tease them apart, my collaborators and I ask how well adults and kids remember individual properties (a specific circle’s color) versus group properties (approximate cardinality; center of mass) after evaluating sentences with each or every. We find that given sentences like every circle is blue, participants recall group properties for the circles, but not for the blue things or even the blue circles. And if each is substituted for every, they recall no group properties at all. This suggests that each has a meaning like (iii) while every has a meaning like (ii). We argue that these representations have consequences for our understanding of the semantic universal “conservativity” and of the ways in which parents use these quantifiers in speech to children.

Precursors of Quantification in Infancy:

When do infants have access to quantificational concepts, like those underlying each and all? So far, we’ve found that even 10 month-olds distinguish collective and distributive exhaustive actions. In particular, they treat videos of three chevrons chasing a single ball together as different in kind from perceptually similar videos in which three chevrons each individually chase their own ball. Follow-up experiments are underway to control for low-level perceptual differences (e.g., spatial dispersion) and to relate these findings to the working memory literature: if infants treat the agents of chasing as a single group in the collective videos, there should be no limit to the number of chevrons they can represent; if they treat the agents of chasing as individuals in the distributive videos, their working memory should become overloaded as more chevrons are added. We’ve also started looking for evidence that infants have access to other quantificational concepts (e.g., can they learn monotonic and antitonic functions?)

Majority Quantifiers:

In a picture with 8 yellow dots and 12 blue dots, both of these sentences are true:
(1) most of the dots are blue.
(2) more of the dots are blue.
But while (1) calls for comparing the number of blue dots to the total number of dots, (2) calls for comparing the blue and yellow dots directly. My collaborators and I argue that these subtle differences in meaning influence how adults and children expect visual scenes to look (e.g., given (1), they create pictures like A but given (2), they create pictures like B), what information they remember from those scenes (they encode only the set of blue dots given (1) but encode both blue and yellow given (2)), and how easily they are able to judge the sentence as true (evaluating (2) is easier, since direct comparisons introduce less noise than proportional comparisons). Together, these effects demonstrate that more and most have discoverable decompositional mental representations that are (at least largely) shared across speakers of English at a fine-grained level of representational detail. We've recently started to extend these predictions to Cantonese majority quantifiers as well.

Event Concepts & Syntactic Bootstrapping:

Learners use the syntactic context of a word to help narrow down their hypothesis space about its meaning. For example, they relate syntactic arguments and event participants in verb learning. But what is the nature of this relation? Do they expect the number of participants perceived in an event to match one-to-one the number of arguments in the clause describing that event? Or do they exploit knowledge of more sophisticated relationships and expect that particular argument positions will name certain participant roles? To this end, we’ve identified events -- like a girl taking a truck from a boy -- that infants plausibly view under a 3-participant concept but that adults often describe with transitive clauses like "The girl took the truck" (without mentioning from whom). We’re using these videos to test how young learners' hypotheses about novel verb meanings change depending on the syntactic frame in which they’re presented.

Output

Papers

T. Knowlton, J. Trueswell, and A. Papafragou (under review) Non-conservative quantifiers are unlernable.

L. Perkins, T. Knowlton, A. Williams, and J. Lidz (under review) Thematic content, not number matching, drives syntactic bootstrapping. [draft on lingbuzz]

D. Odic, T. Knowlton, A. Wellwood, P. Pietroski, J. Lidz, and J. Halberda (forthcoming) Observers efficiently extract the min and max element in perceptual magnitudes sets: evidence for a bipartite format. Psychological Science. 

T. Knowlton and F. Schwarz (forthcoming) "Every" provides an implicit comparison class when "each" does not. Proceedings of the 47th annual Penn Linguistics Conference. 

T. Knowlton, J. Halberda, P. Pietroski, and J. Lidz (2023) Individuals versus ensembles and “each” versus “every”: linguistic framing affects performance in a change detection task. Glossa Psycholinguistics. 

T. Knowlton, P. Pietroski, A. Williams, J. Halberda, and J. Lidz (2023) Psycholinguistic evidence for restricted quantification. Natural Language Semantics. 

T. Knowlton, J. Trueswell, and A. Papafragou (2023) Keeping quantifier meaning in mind: connecting semantics, cognition, and pragmatics. Cognitive Psychology. 

J. Ongchoco, T. Knowlton, and A. Papafragou (2023) Language shifts the representation of sounds in time: from auditory individuals to auditory ensembles. Proceedings of CogSci. 

T. Knowlton, J. Trueswell, and A. Papafragou (2022) New evidence for the unlearnability of non-conservative quantifiers. Proceedings of the 23rd Amsterdam Colloquium. 

T. Knowlton, J. Trueswell, and A. Papafragou (2022) A mentalistic semantics explains "each" and "every" quantifier use. Proceedings of CogSci. 

T. Knowlton and V. Gomes (2022) Linguistic and non-linguistic cues to acquiring the strong distributivity of "each". Proceedings of the LSA. 

T. Knowlton, P. Pietroski, J. Halberda, and J. Lidz (2022) The mental representation of universal quantifiers. Linguistics and Philosophy. 

T. Knowlton, T. Hunter, D. Odic, A. Wellwood, J. Halberda, P. Pietroski, and J. Lidz (2021) Linguistic meanings as cognitive instructions. Annals of the New York Academy of Sciences. 


T. Knowlton, P. Pietroski, A. Williams, J. Halberda, and J. Lidz (2021) Determiners are "conservative" because their meanings are not relations: evidence from verification. Proceedings of SALT. 

Dissertation

T. Knowlton (2021) The psycho-logic of universal quantifiers. University of Maryland. 

Talks

[Upcoming] T. Knowlton (2023) Quantifiers and learnability: uncovering the natural logic behind natural language. Cognitive Development Center Seminar Series, Central European University. 

[Upcoming] T. Knowlton (2023) Universal quantifiers: logically equivalent, psychologically distinct. Linguistics and Cognitive Science Colloquium, University of Delaware. 

T. Knowlton (2023) Universal quantifiers, objects, and ensembles: a case study in psychosemantics. 19th Workshop on Syntax, Semantics and Phonology, Nantes Université. 

T. Knowlton (2023) The poverty of the stimulus in the animal kingdom (humans included). 19th Workshop on Syntax, Semantics and Phonology (pre-workshop course), Nantes Université. 

T. Knowlton (2023) Different determiners invite different ways of restricting and representing the domain. The New York Philosophy of Language Workshop. 

T. Knowlton and F. Schwarz (2023) "Every" provides an implicit comparison class when "each" does not. PLC47, University of Pennsylvania. 

T. Knowlton, J. Trueswell, and A. Papafragou (2023) Non-conservative quantifiers are unlernable. LSA Annual Meeting, Denver. 

T. Knowlton, J. Trueswell, and A. Papafragou (2022) New evidence for the unlearnability of non-conservative quantifiers. 23rd Amsterdam Colloquium, Amsterdam. 

V. Gomes, T. Knowlton, A. Papafragou, and J. Trueswell (2022) Differentiating universal quantifiers by differentiating their domains. BUCLD47, Boston University. 

T. Knowlton (2022) Non-conservative quantifiers are unlernable (and what that means for semantic theory). Psycholinguistics Workshop, UMass Amherst. 

T. Knowlton, J. Trueswell, and A. Papafragou (2022) A mentalistic semantics explains "each" and "every" quantifier use. CogSci 2022, Toronto. 

N. Cesana-Arlotti, T. Knowlton, J. Lidz, and J. Halberda (2022) Universal quantification without language? Ten-month-old infants represent the exhaustivity of a relation in visually presented events. 3rd SPP/ESPP, Milan. 

N. Cesana-Arlotti, T. Knowlton, J. Lidz, and J. Halberda (2022) On the origins of universal quantification: 10-month-old infants represent the exhaustivity of multi-agent intentional actions. XXIII ICIS, Ottawa. 

T. Knowlton (2022) Every universal is first-orderizable, but only "each" is first-orderized. Cognitive Semantics and Quantities Workshop, University of Amsterdam. 

T. Knowlton and V. Gomes (2022) Linguistic and non-linguistic cues to acquiring the strong distributivity of "each". LSA Annual Meeting, Washington, DC. 

T. Knowlton (2021) The psycho-logic of "each" and "every". LingLangLunch, Brown University. 

T. Knowlton, J. Halberda, P. Pietroski, and J. Lidz (2021) Evaluating “each”- (but not “every”-) sentences encourages encoding individual properties. 34th CUNY Conference, UPenn. 

T. Knowlton (2021) The psycho-logic of universal quantifiers. Linguistics Colloquium, USC. 

T. Knowlton and J. Lidz (2021) Bootstrapping universal quantifiers: the role of genericity. LSA Annual Meeting, San Francisco, CA. 

T. Knowlton and J. Lidz (2020) Genericity signals the difference between "each" and "every" in child-directed speech. BUCLD45, Boston University. 

T. Knowlton, P. Pietroski, A. Williams, J. Halberda, and J. Lidz (2020) Memory for cardinality supports a non-relational account of conservativity. ELM1, UPenn. 

N. Cesana-Arlotti, T. Knowlton, J. Lidz, and J. Halberda (2020) An investigation of the origins of logical quantification: infants’ (and adults’) representations of exhaustivity in collective or individual complex actions. XXII ICIS, Glasgow. 

T. Knowlton, P. Pietroski, A. Williams, J. Halberda, and J. Lidz (2020) Conservative meanings with only one set: evidence from verification. 33rd CUNY Conference, UMass. 

T. Knowlton (2019) The psychological treatment of (universal) quantification. Integrated Language Sciences and Technology Seminar, UPenn. 

T. Knowlton, P. Pietroski, J. Halberda, and J. Lidz (2019) The mental representation of universal quantifiers: evidence from verification. 32nd CUNY Conference, CU Boulder. 

T. Knowlton, J. Halberda, P. Pietroski, and J. Lidz (2018) Acquiring the universal quantifiers: every part together or each part on its own? BUCLD 43, Boston University. 

T. Knowlton (2018) Are natural language quantifiers first- or second-order? McDonnell Network Focused Workshop on “The Development of Set and Quantifier Representations”, Johns Hopkins. 

Posters (& talks)

J. Ongchoco, T. Knowlton, and A. Papafragou (2023) Language Shifts the representation of sounds in time: from auditory individuals to auditory ensembles. CogSci 2023, Sydney. 

T. Knowlton and F. Schwarz (2023) "Every" provides an implicit comparison class when "each" does not. 36th HSP, University of Pittsburgh. 

N. Cesana-Arlotti, T. Icard, T. Knowlton, J. Lidz, P. Pietroski, and J. Halberda (2023) The slower they swim, the faster they fly! Can preverbal infants learn antitonic functions? BCCCD23, Budapest. 

T. Knowlton, J. Trueswell, and A. Papafragou (2022) Non-conservative quantifiers are unlearnable. BUCLD47, Boston University. 

T. Knowlton, J. Trueswell, and A. Papafragou (2022) A psycho-semantic explanation of "each" and "every" quantifier use. ELM2, UPenn. 


T. Knowlton, J. Trueswell, and A. Papafragou (2022) Psycho-semantic representations explain "each" and "every" quantifier use. 35th HSP, UCSC/Virtual. 

N. Cesana-Arlotti, T. Knowlton, J. Lidz, and J. Halberda (2021) An Investigation of the origins of logical quantification: infants' (and adults') representations of exhaustivity in collective or individual complex actions. SPP 47, Virtual. 

N. Cesana-Arlotti, T. Knowlton, J. Lidz, and J. Halberda (2021) Representing the exhaustivity of collective and individual actions: an investigation of universal quantification in adults and infants. DUCOG, Virtual. 

T. Knowlton, P. Pietroski, A. Williams, J. Halberda, and J. Lidz (2020) Determiners are "conservative" because their meanings are not relations: evidence from verification. SALT 30, Cornell. 



N. Cesana-Arlotti, T. Knowlton, J. Lidz, P. Pietroski, and J. Halberda (2019) Concepts of universal quantification ("each" and "all") may support infant and adult understanding of collective and distributive actions. CDS 11th Biennial Meeting, Louisville, KY. 

T. Knowlton, J. Halberda, P. Pietroski, and J. Lidz (2019) A novel memory task reveals early understanding of quantifier meanings. SRCD Biennial Meeting, Baltimore, MD. 

T. Knowlton, P. Pietroski, J. Halberda, and J. Lidz (2019) Representational format and universal quantifiers. LSA Annual Meeting, New York, NY. 

L. Perkins, T. Knowlton, A. Williams, and J. Lidz (2018) Matching number vs. linking roles: using 3-participant scene percepts to understand infants’ bootstrapping. BUCLD 43, Boston University. 

T. Knowlton, L. Perkins, A. Williams, and J. Lidz (2018) Getting a grip on infants’ event representations: participant number in TAKE and PICK-UP. XXI ICIS, Philadelphia, PA. 

T. Knowlton, A. Wong, J. Halberda, P. Pietroski, and J. Lidz (2018) Different determiners, different algorithms: two majority quantifiers in Cantonese bias distinct verification strategies. 31st CUNY Conference, UC Davis. 

T. Knowlton, J. Halberda, P. Pietroski, and J. Lidz (2017) Sentences, centers, and sets: set selection and the meanings of more and most. CDS 10th Biennial Meeting, Portland, OR. 

T. Knowlton, J. Halberda, P. Pietroski, and J. Lidz (2017) Distinguishing first- from second-order specifications of each, every, and all. The Seventh MACSIM, Georgetown. 

T. Knowlton, J. Halberda, P. Pietroski, and J. Lidz (2017) Set selection and storage reflect differences in quantifier meanings. McDonnell Network Plenary Workshop on “The Ontogenetic Origins of Combinatorial Thought”, UCSD. 

L. Perkins, T. Knowlton, M. Hirzel, R. Dudley, A. Williams, and J. Lidz (2017) Linguistic and conceptual structure in verb learning. McDonnell Network Plenary Workshop on “The Ontogenetic Origins of Combinatorial Thought”, UCSD. 

Teaching

Courses instructed:

Spring 2020: Language and Thought (LING449T)
Does language shape cognition? Do the details of our native language(s) determine how we perceive the world? Can learning language give us access to new concepts? In this course, we’ll explore these questions through case studies, including color categorization, spatial frames of reference, navigation, theory of mind, event representations, and number. Along the way, we’ll discuss the nature of concepts as well as ways that linguists can leverage the relationship between language and thought to study natural language meaning.

Courses TAed:

Fall 2019: Grammar and Meaning (LING410; Instructor: Valentine Hacquard)
Spring 2019: Child Language Acquisition (LING444; Instructor: Jeffrey Lidz)
Fall 2018: Language and Mind (LING240; Instructor: Tonia Bleam)
Spring 2018: Introductory Linguistics (LING200; Instructor: Tonia Bleam)

Contact Info

  • Email

    tzknowlt@upenn.edu
  • Address

    252 Stephen A. Levin Building
    425 S. University Ave
    Philadelphia, PA 19104

Check out what my awesome cohort from UMD Ling is up to:
Sigwan Thivierge, Mina Hirzel, Anouk Dieuleveut, Aaron Doliana, and Rodrigo Ranero.