Maria A. Babyonyshev In Memoriam* David Pesetsky Maria Babyonyshev died on Friday, March 18, 2011, at the shockingly untimely age of 44, from complications of a devastating 2006 car accident caused by an out-of-control motorcyclist. Masha received her undergraduate degree in linguistics from MIT in 1990, where she completed a major in "Language and Mind," which combined linguistics with cognitive science. (She was elected to Phi Beta Kappa in recognition of her academic achievements.) After a year in the graduate program at Brandeis, she returned to MIT as a graduate student in linguistics. There she received her Ph.D. in 1996, with a dissertation entitled Structural connections in syntax and processing: Studies in Russian and Japanese (Babyonyshev 1997). Ted Gibson and I were privileged to co-advise this dissertation, as part of an unusually large interdisciplinary dissertation committee that also included Alec Marantz, Shigeru Miyagawa, and Ken Wexler. As it happens, the phrase "structural connections" in her dissertation title describes Masha's varied and influential career with singular aptness. Over the scant decade or so in which Masha participated fully in linguistic research, she explored a multitude of links between linguistic theory, language acquisition, and processing—while simultaneously exploring many other links between the structure of her native language, Russian, and other languages of the world. After completing her Ph.D., Masha taught linguistics at Harvard and conducted post-doctoral research on language acquisition in Ken Wexler's lab at MIT. In 2000, she took up a position as Assistant Professor of Linguistics at Yale, where she taught, conducted her research, and advised a growing group of graduate students. The quality, quantity, and diversity of Masha's contributions during her short career is nothing short of remarkable. They include significant novel discoveries about the structure of Russian, empirical contributions to debates about language acquisition, and the very first [End Page 165] steps towards the understanding of the manifestations of Specific Language Impairment among speakers of Russian. Highly regarded as a perceptive and creative syntactician, many of Masha's most important contributions concerned semantics. Though the structure of Russian was her most abiding interest, some of her most interesting work concerned Japanese. A crackerjack theoretician, she was also a pioneer in the integration of developmental and psycholinguistic research with linguistic theory. By the time of the 2006 accident, Masha was focusing quite intensely on argument structure and argument-changing operations in Russian from a developmental perspective (while continuing to make side contributions in a variety of related and unrelated areas)—and had embarked on an extraordinary investigation of Specific Language Impairment (SLI) among Russian speakers that promised to shed unusual light on these topics. This research program developed themes already detectable in her MIT dissertation. To appreciate Masha's achievement, it is worth tracing the thread in her research that led to the SLI project. Her dissertation contained two sections: one devoted to theoretical syntax, and one devoted to sentence processing. The theoretical section was an extended investigation of the so-called "EPP" (Extended Projection Principle) requirement on clauses and its status in Russian. The central case of the EPP cross-linguistically is the requirement that "subject position" (the specifier position of the clause) must be filled—a controversial issue for Russian. In her dissertation, Babyonyshev concerned herself with both syntactic and semantic consequences of this requirement, devoting particular attention to its interaction with case and agreement in the Russian Genitive of Negation construction—which, she argued, supported the idea that the EPP is indeed active in Russian, contrary to appearances. As most readers of this journal will know, the use of genitive rather than nominative or accusative case in this construction has complex consequences for its semantics. Babyonyshev argued that these consequences could be explained on the basis of independently motivated syntactic and semantic proposals if we view the genitive nominals in this construction as caseless, in contrast to their nominative and accusative counterparts. Though case-marked nominals can and must move out of the verb phrase during the course of the derivation, Babyonyshev argued, caseless nominals do not—or at least may not do [End Page 166] so in the same fashion. (Babyonyshev argued that even when...