Aspies are often described as lacking "common sense". A more technical definition of common sense is social instinct. Social instincts are inherited knowlege; things that you "know" without having learned them.
A simple example of a social instinct is flirting. While a neurotypical person will get a feeling when someone is flirting with them, an Aspie will have a hard time telling if someone is interested unless they are directly told. Aspies also have difficulty communicating non-verbally, so even when they can tell someone is interested in them, they can't respond in the subtle indirect ways that is socially expected. That means the Aspie either doesn't communicate their lack of interest (what might be misinterpreted as leading the other person on), or they respond directly, "I'm not attracted to you." Unfortunately, direct communication is sometimes misinterpreted as rude or hurtful.
Another example of a social instinct is deference to authority; the feeling people get that motivates them to obey an authority, even if it is not logical or beneficial to obey. This instinct is why most people would obey a police officer who orders them to step aside when walking down the street, but they are not likely to obey a panhandler that does the same thing. As an Aspie it makes no difference; I'm not going to obey either. From reading Malcolm Gladwell (my favorite author), I learned how obedience to authority can be bad. I feel fortunate that I'm not influenced by the irrational instincts of a neurotypical person. I think the late Pierre Trudeau realized the burden emotional instincts can be in his famous quote, "reason over passion".
Social instinct is the knowledge of previous generations being passed on genetically (most likely epigenetically). So instead of using instinct, Aspies can learn some social behaviors. For instance I have learned to flirt from reading The Game. Now I can enjoy the innocent fun that can be had from flirting. I've also realized that when I'm trying to cash a cheque outside my home branch a little flirting with the teller is much more productive than demanding compliance with the Bills of Exchange Act. And for those who don't know me, yes, I've actually cited the Bills of Exchange Act to bank tellers. More than once. As Homer Simpson would say, "Doh!"