Prolog is an expressive declarative language, and it is the ideal language for learning from structured and complex data. I present some applicatiions of Prolog in this area. First, I iwll discuss applications in the medical domain, such as breast cancer and adverse drug reactions. I will then discuss more complex applications in computational chemistry and in forestry management. To conclude, I’ll go back to the early days of logic programming and discuss the initial steps of an application where Prolog is used together with statistical models to analyse blogs.