One previously unexplained observation about numeral sys-tems is the shared tendency in numeral expressions: Numer-als greater than 20 often have the larger constituent numberexpressed before the smaller constituent number (e.g., twenty-four as opposed to four-twenty in English), and systems thatoriginally adopt the reverse order of expression (e.g., four-and-twenty in Old English) tend to switch order over time. Toexplore these phenomena, we propose the view of Rapid In-formation Gain and contrast it with the established theory ofUniform Information Density. We compare the two theoriesin their ability to explain the shared tendency in the orderingof numeral expressions around 20. We find that Rapid Infor-mation Gain accounts for empirical patterns better than the al-ternative theory, suggesting that there is an emphasis on infor-mation front-loading as opposed to information smoothing inthe design of large compound numerals. Our work shows thatfine-grained generalizations about numeral systems can be un-derstood in information-theoretic terms and offers an opportu-nity to characterize the design principles of lexical compoundsthrough the lens of informative communication.

A scientist’s academic pursuit can follow a winding path.Starting with one topic of research in earlier career, one maylater pursue topics that relate remotely to the initial point.Philosophers and cognitive scientists have proposed theoriesabout how science has developed, but their emphasis is typi-cally not on explaining the processes of innovation in individ-ual scientists. We examine regularity in the emerging order of ascientist’s publications over time. Our basic premise is that sci-entific papers should emerge in non-arbitrary ways that tend tofollow a process of chaining, whereby novel papers are linkedto existing papers with closely related ideas. We evaluate thisproposal with a set of probabilistic models on the historicalpublications from 70 Turing Award winners. We show that anexemplar model of chaining best explains the data among thealternative models, mirroring recent findings on chaining in thegrowth of linguistic meaning.

One of the most influential modern theories of morality, Moral Foundations Theory, proposes that morality is formed on innate and shared modular foundations. Psychologists have studied the conceptual development of these moral foundations in childhood, but there exists no comprehensive effort on characterizing the early emergence of moral foundations in naturalistic settings. We explore the emerging order of moral foundations through child and caretaker speech. Using computational methods, we contribute an annotated dataset of moral utterances and find that the individualizing foundations emerge earlier than the binding foundations. Furthermore, caretakers tend to talk more about fairness and degradation, while children talk more about cheating. These results are robust across child gender, family's social class, and race.