  Human intelligence and human consciousness emerge gradually during the
process of cognitive development. Understanding this development is an
essential aspect of understanding the human mind and may facilitate the
construction of artificial minds with similar properties. Importantly, human
cognitive development relies on embodied interactions with the physical and
social environment, which is perceived via complementary sensory modalities.
These interactions allow the developing mind to probe the causal structure of
the world. This is in stark contrast to common machine learning approaches,
e.g., for large language models, which are merely passively ``digesting'' large
amounts of training data, but are not in control of their sensory inputs.
However, computational modeling of the kind of self-determined embodied
interactions that lead to human intelligence and consciousness is a formidable
challenge. Here we present MIMo, an open-source multi-modal infant model for
studying early cognitive development through computer simulations. MIMo's body
is modeled after an 18-month-old child with detailed five-fingered hands. MIMo
perceives its surroundings via binocular vision, a vestibular system,
proprioception, and touch perception through a full-body virtual skin, while
two different actuation models allow control of his body. We describe the
design and interfaces of MIMo and provide examples illustrating its use. All
code is available at https://github.com/trieschlab/MIMo .
