Bjarnadóttir, KristínBjarnadóttir, KristínFuringhetti, FulviaKrüger, JennekePrytz, JohanSchubring, GertSmid, Harm Jan2025-11-202025-11-202019Bjarnadóttir, K 2019, Two textbooks on Unconventional Arithmetic: Reactions of Influential Persons. in K Bjarnadóttir, F Furinghetti, J Krüger, J Prytz, G Schubring & H J Smid (eds), "Dig Where You Stand" 5 : Proceedings of the Fifth International Conference on the History of Mathematics Education. "Dig Where You Stand", vol. 5, Utrecht University - Freudenthal Institute, Utrecht, pp. 65 - 81, The Fifth International Conference on the History of Mathematics Education, Utrecht, Netherlands, 19/09/17.conference978-908-236-796-622146302331fe53bc-0649-4e7b-adb0-3855f9057453https://hdl.handle.net/20.500.11815/6163The paper describes two Icelandic arithmetic textbooks, published respectively in 1780 and 1911– 14, both written at the beginning of an era when enhancing general education was placed on the agenda for restoring the Icelandic society after natural disasters. Both textbooks emphasized unconventional and mental arithmetic. Both books were criticized by influential persons. The focus is on the grounds of their arguments. Both books survived the criticism, considering the circumstances, while few positive comments on them have been found in sources from their times.177018441701844165 - 81eninfo:eu-repo/semantics/restrictedAccessEnlightenment, arithmetic textbooks, mental arithmetic, number tricks, Rule of ThreeGeneral Mathematics/dk/atira/pure/researchoutput/researchoutputtypes/contributiontobookanthology/chapter