Lyfa stammered as she said, and Yui tilted her head, keeping quiet like a teacher who was thinking of how to explain to her students, nodded a bit, then started explaining, “Let’s start from what we have called an AI before— In the last century, the people who developed AIs were aiming for a common goal through two paths. One of them is the ‘top-down-type AI’, and the other is called the ‘bottom-up-type AI’. Asuna pricked up her ears, trying her best to understand the content of the pure and innocent voice that the delicate girl spoke in. “First, regarding the top-down AI, it’s a kind that purely relies on the existing computer architecture to accumulate experience through simple questions and answers, ultimately becoming a real intellectual through learning. Including me, most AIs are all top-down-type, so that means... the ‘knowledge’ I have now may look similar to yours, mama, but it in fact is something completely different. To put it directly, an existence like mine is just a collection of a system that can only ‘Hear a question A and reply with B’.” Yui said that as her clear white cheeks showed some signs of loneliness. Are my eyes playing tricks on me? Asuna thought. “If, how mama asked me ‘What is an AI?’, and how I immediately showed a ‘bitter smile’ or some variation like that, that would be because papa mostly made such an expression, and I gained experience and learned it when I am asked about myself. The basis itself is not really that different from the predictive text app in mama’s portable terminal —because of this, the top-down-type AIs as they currently stand are nowhere near the level of being a real AI. This is the ‘so- called AI’ I just explained to Lyfa-san, so please understand it like that.”