You'd have to find out the veracity of those leading phrases. I'm guessing that it just prefaces the answer with a randomly chosen statement of doubtfulness. The error bar behind every bit of knowledge would have to exist in the dataset.

(And in neural network terms, that error bar could be represented by the number of connections, by congruency of separate paths of arguing, by vividness of memories, etc ... it's not above human reasoning either, no need for new data structures ...)