Pluralistic ignorance
In social psychology, pluralistic ignorance is a situation in which a majority of group members privately reject a norm, but go along with it because they incorrectly assume that most others accept it. This is also described as "no one believes, but everyone thinks that everyone believes". In short, pluralistic ignorance is a bias about a social group, held by the members of that social group.
Paul R. Ehrlich
Dan Gardner argues that Ehrlich has been insufficiently forthright in acknowledging errors he made, while being intellectually dishonest or evasive in taking credit for things he claims he got "right". For example, he rarely acknowledges the mistakes he made in predicting material shortages, massive death tolls from starvation (as many as one billion in the publication "Age of Affluence") or regarding the disastrous effects on specific countries. Meanwhile, he is happy to claim credit for "predicting" the increase of AIDS or global warming. However, in the case of disease, Ehrlich had predicted the increase of a disease based on overcrowding, or the weakened immune systems of starving people, so it is "a stretch to see this as forecasting the emergence of AIDS in the 1980s." Similarly, global warming was one of the scenarios that Ehrlich described, so claiming credit for it, while disavowing responsibility for failed scenarios is a double standard. Gardner believes that Ehrlich is displaying classical signs of cognitive dissonance, and that his failure to acknowledge obvious errors of his own judgement render his current thinking suspect.