“it’s just common sense” is a way to shift the blame onto a person for not knowing, and off of their community for not telling them. if someone doesn’t know “common sense”, literally the last person to blame is the one who is ill-informed
@kasdeya the concept of “common sense” is absolutely a way to shift blame – it’s why it’s so prevalent in neglectful parents to suggest that things that they are tasked with teaching are instead some abstractly available form of knowledge which can be somehow acquired without teaching. presumably the person without the “common sense” should be gleaning this information through contextual clues via exposure to others. this assumption is ableist and, when employed by someone charged with the care of another, frequently blames victims of abuse which tend to be isolated from others (in particular, children).