To understand a joke, you have to belong to the parish, that community of understanding, and if you feel you belong to that community of understanding, of getting the joke, then you will laugh at almost anything that reinforces your sense of belonging to that group.
àquela comunidade de entendimento, e, quando sentimos pertencer a essa comunidade de entendimento, que entende a piada, então, vamos rir de quase tudo que reforce nosso sentimento de pertencimento àquele grupo.