This is why, whether it’s an old friend who invites you to dinner or a boss who asks you to take on an important and high-profile project, or a neighbor who begs you to help with the PTA bake sale, the very thought of saying no literally brings us physical discomfort. We feel guilty. We don’t want to let someone down. We are worried about damaging the relationship. But these emotions muddle our clarity. They distract us from the reality of the fact that either we can say no and regret it for a few minutes, or we can say yes and regret it for days, weeks, months, or even years.
— Essentialism (Greg Mckeown), Loc. 1475–9
A tutorial on how to be an asshole and live only for yourself, lol. That’s one phrase this book can be summarised with.