Passage of legislation in congress requires mutual accommodations. this suggests that congressional behavior is

I think this question showed up here twice on .  I'll refer you to the answer I gave at the other location:
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Basically, the concept the question is referencing is the principle of reciprocity. The principle of reciprocity says that human beings have a need and tendency to want to give something back when something is received.  This give and take approach helps us to work together toward compromises and mutually agreeable solutions.