TITLE:
An Empirical Analysis of Van Manen’s Rule of Three: Sublexical Constraints in ASL Morph Structures
AUTHORS:
Sean Ryan Hauschildt, Kenley Migues, Ja’Nysa Richard, Dymaia Hadnot, Deborah Marshall, Syanne Monroe, Victor Yacovodonato, Ryan Klaudt, Makayla Tucker, Sam Mullan, Edwin Hernandez, Allyson Arnold, Dorothy Miller, Ivana Laura Camarillo, Alycia L. Slattery, Audra McCorkle-Geng, Cristophorus Subandi Budidharma
KEYWORDS:
Fingerspelling, ASL, Rule of Three, Phonology, Signed Language
JOURNAL NAME:
Open Journal of Social Sciences,
Vol.14 No.8,
August
11,
2026
ABSTRACT: Van Manen (2018) proposed the rule of three theory, suggesting that American Sign Language (ASL) morph structures are constrained by a maximum of three sublexical features within phonological domains. However, this claim has not previously been empirically tested. The present study examined whether ASL fingerspelling morph types, unimorph, bimorph, trimorph, quadmorph, synomorph, and typical morph conform to the rule of three constraint across five sublexical domains: handshape, location, movement, palm orientation, and non-manual signals. A dataset of 1579 ASL morph tokens was collected and coded using examples identified in Van Manen’s (2018) framework. Frequency distributions were first calculated to examine the number of structural units within each domain, followed by median analysis to summarize structural complexity across morph types. Exact binomial tests were conducted to compare observed violation rates with a prespecified 5% tolerance threshold. Results indicated that the majority of morph productions conformed to the three-unit constraint. Apparent violations were limited and were associated with specific lexical sequences that likely reflect phonological processes rather than independent structural units.