Satisfaction is to desire as justification, to belief. We may "want to believe" something (we may desire to hold something true) but in the absence of justification the belief will be irrational. Likewise, we may "think we need" something (we may believe we have a right to it) but as the desire is frustrated our passion for it wanes.

We are, ultimately, justified or satisfied, disappointed or frustrated, by experience. We cherish our beliefs, we sustain our desires, according to what we see around us and what we're able to do.

Of course, some desires are inextinguishable, some beliefs incorrigible. We may be frustrated in our pursuit of them and never let them go. We may be forever disappointed by the evidence of our senses and yet continue to believe. One must marvel at our stubbornness sometimes—our loyalty, our bigotry.