We investigate whether performing reasoning in a continuous latent space leads to more robust multilingual capabilities. We compare Continuous Chain-of-Thought (using the CODI framework) against standard supervised fine-tuning across five typologically diverse languages: English, Chinese, German, French, and Urdu. Our experiments on GSM8k and CommonsenseQA demonstrate that continuous reasoning significantly outperforms explicit reasoning on low-resource languages, particularly in zero-shot settings where the target language was not seen during training. Additionally, this approach achieves extreme efficiency, compressing reasoning traces by approximately 29× to 50×. These findings indicate that continuous latent representations naturally exhibit greater language invariance, offering a scalable solution for cross-lingual reasoning.
@article{arxiv.2603.08177,
title = {Is continuous CoT better suited for multi-lingual reasoning?},
author = {Ali Hamza Bashir and Behzad Shomali and Markus Frey and Mehdi Ali and Rafet Sifa and David Berghaus},
journal= {arXiv preprint arXiv:2603.08177},
year = {2026}
}