Full Idea
Besides wanting to fulfil his desire, the person who cares about what he desires wants something else as well: he wants the desire to be sustained.
Gist of Idea
People want to fulfill their desires, but also for their desires to be sustained
Source
Harry G. Frankfurt (The Reasons of Love [2005], 1.6)
Book Reference
Frankfurt,Harry G.: 'The Reasons of Love' [Princeton 2006], p.16
A Reaction
Plato, in 'Gorgias', makes this fact sound like a nightmare, resembling drug addiction, but in Frankfurt's formulation it looks like a good thing. If you want to make your family happy because you love them, you would dread finding your love had died.