أحيانًا يتمسّك الناس بمعتقدٍ جوهريّ راسخ. فإذا عُرضت عليهم أدلّةٌ تناقضه، لم يستطيعوا قبول الدليل الجديد، لأنه يولّد شعورًا بالضيق الشديد يُسمّى التنافر المعرفي. ولأنّ حماية المعتقد الجوهري أمرٌ بالغ الأهمية عندهم، فإنهم يبرّرون كل ما لا يتّسق معه، ويتجاهلونه، بل ينكرونه.

“Sometimes people hold a core belief that is very strong. When they are presented with evidence that works against that belief, the new evidence cannot be accepted. It would create a feeling that is extremely uncomfortable, called cognitive dissonance. And because it is so important to protect the core belief, they will rationalize, ignore and even deny anything that doesn't fit in with the core belief.”Frantz Fanon