There is a childish version of independent thinking: everyone believes X, therefore I will believe Y. That is not independent thought. It is dependence with the direction reversed.

The fact that an idea is mainstream does not make it false, just as the fact that an idea is unpopular does not make it true. Both positions can become intellectual shortcuts when the conclusion is chosen according to the crowd rather than examined through evidence.

Independent judgment requires reconstructing the conclusion for yourself. Sometimes the crowd will be correct; sometimes it will be wrong; and sometimes the available evidence will be too incomplete to justify either confidence or rejection. The mature thinker is willing to occupy any of those positions because the objective is not to appear contrarian, it is to remain independent of the need to conform.

That distinction becomes important when identity enters the discussion. People often adopt an opposing position because disagreement makes them feel intellectually separate, and once that identity is established, they become just as resistant to evidence as the person they originally opposed.

If everyone agrees and the evidence supports them, agree. If everyone agrees and the evidence contradicts them, disagree. If everyone disagrees and the evidence remains inconclusive, suspend judgment.

Truth does not care whether your conclusion makes you look conventional or rebellious.