On 30 October 2026, I had the pleasure of serving as external examiner for the PhD defense of Ponrawee Prasertsom at the Center for Language Evolution, University of Edinburgh. The thesis, “Explaining Constrained Variation of Linguistic Forms and Meanings: Experimental and Computational Approaches,” was supervised by Jennifer Culbertson and Kenny Smith. It asks why some kinds of linguistic systems are common, and others never occur, and uses behavioral experiments and computational modeling to answer it. It shows that a preference to categorize by animacy rather than color can be explained by general principles of categorization. It also shows that recursive numeral systems are shaped by a pressure for regularity and generalisability, and it tests what the Rational Speech Act model predicts about how a word’s cost shapes the lexicon. It was a genuinely enjoyable and stimulating discussion, and a pleasure to examine together with Simon Kirby. Congratulations, Dr Prasertsom!
PhD Defense in Edinburgh
