The phrase “know how to say no” is often interpreted as “say no” or “courage to say no,” but this is not the case. There are people who are quick to say No to everything, and even if they eventually say Yes, they are left feeling uncomfortable by having “said No first”. There is no need to refuse outright as such. Let the disappointment come gradually. You will destroy their dependence on you, so leave some hope to soften the impact. Substitute your act with courtesy.
from The Art of Worldly Wisdom Know how to say no. lxx
One should not give way to anything or anyone. Therefore, knowing how to refuse is just as important as knowing how to agree. This is especially true of persons in positions of authority. It all depends on the method. One person’s “no” can be considered more important than another’s “yes.” There are people who always say No, and they hate everything because of it. For them, the No always comes first, and even if they do eventually give in, it is never good because of the unpleasant foreboding. Your refusal does not have to be outright: let the disappointment come gradually. It will destroy the dependence. Leave some spice of hope to soften the rejection. You can supplement politeness and let respectable words take the place of deeds. Say yes and no quickly, but think long and hard.
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