Background, Examples and Hypothesis:
Now we will switch off with three logic programs. So very firstly, we will have the logic program representing a set of positive examples for the concept that we wish to be learned, and we denote the set of examples E+. And other secondly we will have a set of negative examples for the concept that we wish to be learned or labelled E-. And now thirdly that we will have set of Horn clauses so that provide background concepts, and hence we denote this logic program B. In fact we will denote the logic program representing the learned hypothesis H.
On average, E+ and E- will be ground facts, i.e. like Horn clauses with no body. Generally in this case there we can prove that an example of E follows from the hypothesis so as they are all still logic programs. Where an example as positive or negative is proved to be true using a hypothesis H then we say that there H as taken along with B with explains the example.