¹²(Singh et al., 2010) One might ask whether such curiosity could not be learned by the agents as part of the reinforcement learning process. That might be possible in principle, but it would probably take too long. An animal would learn to be curious when it has reached a certain age, but it is probably more useful for animals to be curious when they are young, as tends to be the case in biology. In AI, researchers also assume that such curiosity must be explicitly programmed.