Even in conventional programming it seems easier to ask about a famous person’s parents than vice versa. A name is an ambiguous pointer so if someone says “Tom Cruise” you’d generally just look for the most famous person of all the people who have that name and answer the question for that individual. But to do the reverse you have to figure out that no “Mary Lee Pfeiffer” is famous enough on their own to be the target of the search and then go on to search through all the children of all the people named “Mary Lee Pfeiffer”, notice that one is really famous, and then answer with that result.
Even in conventional programming it seems easier to ask about a famous person’s parents than vice versa. A name is an ambiguous pointer so if someone says “Tom Cruise” you’d generally just look for the most famous person of all the people who have that name and answer the question for that individual. But to do the reverse you have to figure out that no “Mary Lee Pfeiffer” is famous enough on their own to be the target of the search and then go on to search through all the children of all the people named “Mary Lee Pfeiffer”, notice that one is really famous, and then answer with that result.