The main conceptualization these days is that in the process of understanding information, one must first believe the information and only later is one able to negate or falsify it. Thus, negation is considered a secondary process, demanding awareness and cognitive resources, and it also carries a risk of failure, resulting in gullibility. In my talk I will review empirical research demonstrating the existence of two models for the negation process, suggesting that while one may lead to gullibility, the other offers a strong and successful negation process that diminishes gullibility effects such as false memory and misinformation. Further studies reveal that contextual cues or personality dispositions may induce a skeptical mindset in which the successful negation process is spontaneous, serving as the default response and reducing any gullibility effects. These studies lead to the conclusion that there is both a gullible mindset in which acceptance is the primary process and a skeptical mindset in which rejection is the primary process. The mindsets alter according to context and individual differences regarding trust. Critically, in a skeptical mindset, one’s initial response is to reject information. The skeptical mindset offers new insights regarding cognitive antecedents of the post-truth era.