The quote from John Boyne's book, The Absolutist, reflects a common sentiment where individuals prefer to dismiss concerns about others' issues. They do so to avoid ruining their own day with unnecessary worries, even if their reasoning is based on ignorance or lack of understanding.
It highlights a tendency to prioritize oneself over empathy, using a dismissive attitude as a shield against potential emotional disturbances. This attitude may stem from a desire to protect personal peace by avoiding engagement with the problems of others.