Advantages:
Some historians have suggested that two-party systems promote centrism and encourage political parties to find common positions which appeal to wide swaths of the electorate. It can lead to political stability which leads, in turn, to economic growth.
Disadvantages:
Two-party systems have been criticized for downplaying alternative views, being less competitive, encouraging voter apathy since there is a perception of fewer choices, and putting a damper on debate within a nation.
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