Every now and then, I hear or see someone that strikes me as having strong natural intelligence. In this country today, there are many tools, groups and tendencies to promote and feed a mind that seeks knowledge on every side. I think it happens naturally that as a person ages, questioning naturally appears. Often educators talk about "critical thinking" but in America today, it is possible to get the idea that advanced thinking is about the same as immediately doubting everything. If I am male, I may go through stages of development that seek contest and competition, as a type of sport and a seeking after championship and praise.
Longtime assurances, basic creeds and fundamental convictions can be examined carefully. Sometimes, they don't emerge from careful examination looking as good and shiny as they always did in one's past. A basic examination can take place explicitly but one can also develop more or less underground, as it were. If examination causes fundamental questions of ideas or convictions or loyalties that have always served as foundational, the result can feel threatening and disorienting. If it seems that basic pillars of one's life are threatening to collapse or change in a fundamental way, the situation is sometimes described as an existential crisis.
If I look up existential crisis in Google, I find 35 million results in about half a second. Developing deep doubts about a question, an issue or a conviction can be handled better if the person experiencing it, realizes the experience as something that happens to many good, strong, healthy minds in today's world. There are many ways to go about helping one's self including writing questions and subjects of interest down.
