cynicism

Unlike the old philosophy of Cynicism (which included living "in agreement with Nature" ... and a few sillier things, some of which may have been taken up by early neochristianity), modern  cynicism is far less noble. In fact, I am tempted to define it with links along the lines of http://www.oxforddictionaries.com/definition/english/stupidity, but is really more about evading or surrendering  responsibility, perhaps out of despair or being overwhelmed by the size of a task facing one, which, whilst understandable, is basically irresponsible. The exception to that is people who are fashionably cynical, perhaps out of a very much mistaken opinion that it makes them somehow look intelligent or informed, or to create a sense of belonging (that is based on something unhealthy): for those people, my best definition of cynicism is http://www.oxforddictionaries.com/definition/english/stupidity.

A recent example of the sort of outcomes that one can expect from cynicism is the myth that Brexit was attributable to too few young people turning out to vote: we actually don't know how many young people voted, but the notion that cynicism could have led to that outcome is a very valuable example of the fundamental problem of cynicism.

If there is a valid basis to a belief - GENUINELY valid, based on objective evidence, then the matter is no longer, as far as I am concerned, a matter of cynicism.

See also what I've written about conspiracy nuts (who also have the same qualification - i.e., if there is genuine, objective evidence, of the sort an investigate journalist would uncover (e.g., Watergate], it is not a conspiracy theory; also, some so-called conspiracy theories are actually an awareness of what is happening psychically, with earthbound entities and those using psychic control, and the presentation of them as physical is mistaken and, ultimately, stupid).