There are many formal definitions of (machine) learning. For example, see: A Theory of the Learnable L. G. Valiant 1984 https://web.mit.edu/6.435/www/Valiant8

There are many formal definitions of (machine) learning. For example, see: A Theory of the Learnable L. G. Valiant 1984 https://web.mit.edu/6.435/www/Valiant84.pdf https://web.mit.edu/6.435/www/Valiant84.pdf Also: Statistical Learning Theory Vladminir N. Vapnik, 1998 https://www.wiley.com/en-us/Statistical+Learning+Theory-p-9780471030034 https://www.wiley.com/en-us/Statistical+Learning+Theory-p-97... And: Language identification in the limit E. Mark Gold, 1964 https://www.sciencedirect.com/science/article/pii/S0019995867911655 https://www.sciencedirect.com/science/article/pii/S001999586...