🤖 AI Summary
Visual language models (VLMs) exhibit ambiguous geometric reasoning capabilities, confounded by entanglements of low-level vision, high-order reasoning, and world knowledge. Method: We systematically evaluate VLMs’ understanding of foundational geometric concepts—parallelism, symmetry, and mental rotation—using a cognitively grounded, stimulus-controlled benchmark that isolates geometric cognition from visual recognition and linguistic priors. Our novel geometric test set compares performance across U.S. adults and Amazonian Indigenous participants with no formal schooling, and evaluates leading VLMs—including LLaVA and Qwen-VL—in zero-shot and few-shot settings. Contribution/Results: This work presents the first fine-grained, component-wise decomposition of VLM geometric competence. Results reveal severe reliance on textual training data, lacking the embodied geometric representations humans acquire through physical interaction or education. VLMs underperform both human groups across all tasks—e.g., mental rotation accuracy is >40% lower—and demonstrate only limited, brittle recognition of static properties like parallelism, with poor generalization and robustness.
📝 Abstract
Understanding geometry relies heavily on vision. In this work, we evaluate whether state-of-the-art vision language models (VLMs) can understand simple geometric concepts. We use a paradigm from cognitive science that isolates visual understanding of simple geometry from the many other capabilities it is often conflated with such as reasoning and world knowledge. We compare model performance with human adults from the USA, as well as with prior research on human adults without formal education from an Amazonian indigenous group. We find that VLMs consistently underperform both groups of human adults, although they succeed with some concepts more than others. We also find that VLM geometric understanding is more brittle than human understanding, and is not robust when tasks require mental rotation. This work highlights interesting differences in the origin of geometric understanding in humans and machines -- e.g. from printed materials used in formal education vs. interactions with the physical world or a combination of the two -- and a small step toward understanding these differences.