A few hundred years ago, people had a simple explanation for everything: God did it, caused it or allowed it.
Then with the renaissance and enlightenment, natural science came to the fore, and people began to want a rational explanation for everything. And when that rational, logical explanation isn’t forthcoming, then an explanation has to be found, even if it makes no sense.
That, in summary, is what conspiracy theories are all about, ranging from the Knights Templar in the 12th century, to Flight 370.
In any traumatic event that produces emotional responses, we want an explanation. But sometimes life is not that simple, and explanations are difficult to come by. It is a lack of information that fuels conspiracy theories.
Add to this lack of information a general distrust of politicians, government and business and it easy to see how rumors and speculation grow.
There is also a tendency to not believe that a major event could have a simple cause. When a president is assassinated or a city attacked, we have a hard time believing that a lone gunman or a few terrorists could carry out such far-reaching events.
Humans also have a hard time believing in randomness. Again, with the advent of a high degree of certainty in the natural sciences, we have come to expect such inevitability in the social sciences as well. Thus we seek explanations and certitude where there may not be any.
In addition, we tend to downplay the role of chance in serious events. Sometimes things just break and sometimes people do bad things by themselves. Yes, there may be an underlying cause, but it is probably not big business, big government or big anything else.
Occam’s razor says that if there are two explanations, the simplest is probably the correct one. Carl Sagan said that extraordinary claims require extraordinary evidence. Hanlon’s Law says never attribute to malice what can be better explained by incompetence. And my favorite, a quip that or may not have been made by Sigmund Freud, sometimes a cigar is just a cigar.