Deep Symbolic Learning: Discovering Symbols and Rules from Perceptions

Deep Symbolic Learning: Discovering Symbols and Rules from Perceptions

Alessandro Daniele, Tommaso Campari, Sagar Malhotra, Luciano Serafini

Proceedings of the Thirty-Second International Joint Conference on Artificial Intelligence
Main Track. Pages 3597-3605. https://doi.org/10.24963/ijcai.2023/400

Neuro-Symbolic (NeSy) integration combines symbolic reasoning with Neural Networks (NNs) for tasks requiring perception and reasoning. Most NeSy systems rely on continuous relaxation of logical knowledge, and no discrete decisions are made within the model pipeline. Furthermore, these methods assume that the symbolic rules are given. In this paper, we propose Deep Symboilic Learning (DSL), a NeSy system that learns NeSy-functions, i.e., the composition of a (set of) perception functions which map continuous data to discrete symbols, and a symbolic function over the set of symbols. DSL simultaneously learns the perception and symbolic functions while being trained only on their composition (NeSy-function). The key novelty of DSL is that it can create internal (interpretable) symbolic representations and map them to perception inputs within a differentiable NN learning pipeline. The created symbols are automatically selected to generate symbolic functions that best explain the data. We provide experimental analysis to substantiate the efficacy of DSL in simultaneously learning perception and symbolic functions.
Keywords:
Machine Learning: ML: Neuro-symbolic methods
Knowledge Representation and Reasoning: KRR: Learning and reasoning
Machine Learning: ML: Explainable/Interpretable machine learning