There's nothing implicit in the laws of nature which says that stealing things is wrong, because the laws of nature don't have anything to do with morality. Neither the concept of 'theft' nor the concept of 'wrong' are innate to humans. They have to be taught. The key difference between this idea and Searle's Chinese Room thought experiment is that this idea allows the contents of the 'poster' to be altered by material from the 'IN' slot. Every human starts off with a blank poster, and over the years, it's filled with more and more rules for taking the 'input' of human social interaction and converting it into 'output' – your own participation in that social interaction. So, if we're talking about 'theft' being 'wrong', we have to think about it in terms of the 'input', the 'output', and the 'rules'.
Anyway, all of these 'rules' get used to process the 'input' and eventually the 'output' pops out – let's say, for instance, that you decided to take the banknote and return it to the guy who dropped it. In this case, the rule 'theft is wrong' won out over 'money is something to be acquired'. Every human is fundamentally just 'shuffling symbols' inside the 'box' – mindlessly accepting input and manipulating it according to arbitrary, abstract rules that we only have because 'culture' or 'civilisation' imparts them to us through meta-rules. Internally, there's no such thing as society, or even morality – just rules and meta-rules, which the vast majority of people go about their lives entirely unaware of.
It's not impossible for people to become aware that they exist inside a 'box'. In some cases, they even recognise the nature of rules and meta-rules. People whose process of ideation is no longer unconsciously governed by rules and meta-rules – these people are 'sociopaths'. sociopaths are those who are aware of the arbitrary nature of the rules that govern the nature and method of their human interactions
Yukari is a sociopath.