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PySigma: Towards Enhanced Grand Unification for the Sigma Cognitive Architecture

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Part of the Lecture Notes in Computer Science book series (LNAI,volume 13154)


The Sigma cognitive architecture is the beginning of an integrated computational model of intelligent behavior aimed at the grand goal of artificial general intelligence (AGI). However, whereas it has been proven to be capable of modeling a wide range of intelligent behaviors, the existing implementation of Sigma has suffered from several significant limitations. The most prominent one is the inadequate support for inference and learning on continuous variables. In this article, we propose solutions for this limitation that should together enhance Sigma’s level of grand unification; that is, its ability to span both traditional cognitive capabilities and key non-cognitive capabilities central to general intelligence, bridging the gap between symbolic, probabilistic, and neural processing. The resulting design changes converge on a more capable version of the architecture called PySigma. We demonstrate such capabilities of PySigma in neural probabilistic processing via deep generative models, specifically variational autoencoders, as a concrete example.


  • Sigma
  • Cognitive architecture
  • Probabilistic graphical model
  • Message passing algorithm
  • Approximate inference
  • Deep generative model

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  • DOI: 10.1007/978-3-030-93758-4_36
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Part of the effort depicted is sponsored by the U.S. Army Research Laboratory (ARL) under contract number W911NF-14-D-0005, and that the content of the information does not necessarily reflect the position or the policy of the Government, and no official endorsement should be inferred. We also would like to thank Dr. Paul Rosenbloom for his comments and suggestions, which helped improve the quality of this paper. More importantly, we appreciate Dr. Rosenbloom’s continuous and invaluable guidance in enhancing our understanding of cognitive architectures and the design choices for Sigma.

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Zhou, J., Ustun, V. (2022). PySigma: Towards Enhanced Grand Unification for the Sigma Cognitive Architecture. In: Goertzel, B., Iklé, M., Potapov, A. (eds) Artificial General Intelligence. AGI 2021. Lecture Notes in Computer Science(), vol 13154. Springer, Cham.

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