Bias is a disproportionate weight in favor of or against an idea or thing, usually in a way that is closed-minded, prejudicial, or unfair. Biases can be innate or learned. People may develop biases for or against an individual, a group, or a belief. In science and engineering, a bias is a systematic error. Statistical bias results from an unfair sampling of a population, or from an estimation process that does not give accurate results on average.
There would also be the danger of giving adherence to an ideology which does not rest on a true and organic doctrine, to take refuge in it as a final and sufficient explanation of everything, and thus to build a new idol, accepting, at times without being aware of doing so, its totalitarian and coercive character. And people imagine they find in it a justification for their activity, even violent activity, and an adequate response to a generous desire to serve. The desire remains but it allows itself to be consumed by an ideology which, even if it suggests certain paths to man's liberation, ends up by making him a slave. (Papal Writings, 14 May 1971).