COMMENT Biosemiotics https://doi.org/10.1007/s12304-025-09612-2 Abstract Metacognition—the iterative self-monitoring of thought—is not purely internal, but rather emerges as a second-order semiotic dynamic, deeply entangled with material and semiotic scaffolds, (aligning with Petrilli & Ponzio’s [2025] claim that ‘thanks to metasemiosis the human animal not only operates immediately in semiosis.’) This work reviews the main models on metacognition, culminating in a possible take on metacognition as metasemiosis through Peirce’s active cognitive external- ism. The discussion explores how external sign systems, including language and other semiotic artifacts, form the basis of a second-order semiotic process that re- shapes cognitive architecture. Finally, this Peircean approach is situated in relation to Andy Clark’s extended cognition framework. Keywords Metacognition · Metarepresentation · Metasemiosis · Cognitive externalism · Semiotic externalism · C. S. Peirce The semiotic animal uses “signs about signs about signs” (Morris, 1971 [1949]: 434–455). Thanks to metasemiosis the human animal not only operates imme- diately in semiosis, but can objectify signs critically and creatively, is endowed with imagination, is capable of investigation, reflection, evaluation, delibera- tion. (Petrilli & Ponzio, 2025) Received: 24 March 2025 / Accepted: 2 May 2025 © The Author(s), under exclusive licence to Springer Nature B.V. 2025 Metasemiosis as Extended Second-Order Semiosis: Revising Metacognition Models Henrique Perissinotto 1  · João Queiroz 2 Commentary to the article “Biosemiotics, Global Semiotics and Semioethics” (Petrilli & Ponzio, 2025) DOI: https://doi.org/10.1007/s12304-024-09590-x  João Queiroz joao.queiroz@ufjf.br 1 Communication Department, Federal University of Juiz de Fora (UJFJ), Juiz de Fora, Minas Gerais, Brazil 2 Linguistics Department, Federal University of Juiz de Fora (UJFJ), Juiz de Fora, Minas Gerais, Brazil 1 3