How many people does it take to establish a theory?
There are often theories published by scientists in both the hard sciences and social sciences based on new understanding of fundamental science and better data collecting mechanisms that runs in opposite to the prevailing theories of the day (or it is not politically correct). I am reminded of the case of Darwin and Galileo and many modern cases that presents alternative theory to a side of an argument that has long been thought of as quack science of unsubstantiated conspiracy theories. Science is all about objectivity, if we were to find that "gun ownership decrease gun deaths" or "sexual orientation can be changed later in life" or "our universe is 11 dimensions and made up of little vibrating strings" or "vaccination causes serious and incurable side effects" then scientifically speaking we should accept these results despite that they run counter to our intuition and are not exactly the most politically correct thing to say in our time. In fact, even mentioning this decreases my credibility in some circles. Unfortunately, in some of these cases, when research is done it so happens that in the next few decades it captures little attention (again Galileo) or due to lack of interest or funding, so that there are literally only one or two person on one side of an argument. When presenting these theories to friends or colleagues, I sometimes face scrutiny that this explanation has support from only one or two theorists (especially if those theorists are prominent i.e. Freud, Judith Butler, Zizek, Pew Research, Gallup) so it is not credible. People keep on telling me I should find more and more people to support my argument because "anyone can find quack scientists" or "anyone can find hollow earth supporters". When I find another study that supports a theory, people then tell me I should find even more people because only then "a hypothesis can become an evidence". So how many scientists does it really take to establish a theory? What does it mean to establish a theory? i.e. the theory of gravitation, the theory of evolution. Note: I am asking here because people are significantly more well read and objective than some other forums.