Always someone who can describe it better than I.
Excerpt from Corn-pone Opinions, Mark Twain
“Men think they think upon great political questions, and they do; but they think with their party, not independently; they read its literature, but not that of the other side; they arrive at convictions, but they are drawn from a partial view of the matter in hand and are of no particular value. They swarm with their party, they feel with their party, they are happy in their party’s approval; and where the party leads they will follow, whether for right and honor, or through blood and dirt and a mush of mutilated morals.
We all do no end of feeling, and we mistake it for thinking. And out of it we get an aggregation which we consider a boon. Its name is Public Opinion. It is held in reverence. It settles everything. Some think it the Voice of God.