After the user makes some connections between ideas, the method find_ideas_with_common_friends(idea1), takes the adjacency matrix of the relationships, normalizes the rows, and finds the other ideas (rows) which have the maximum dot product with the given idea, i.e., have the most common neighbors. Note how_related_are_ideas finds related ideas by commonsense reasoning, while find_ideas_with_common_friends finds related ideas using relations inputted by the user.