The phrase "central thesis" refers to the main argument or idea that is being presented or discussed in a piece of writing or a speech. It is the most important point that the author or speaker is trying to convey to the audience. Full definition
That was the fascinating central thesis of the screenplay. (waytooindie.com)
In order to do well on a political science thesis My Thesis Writing Service suggests devoting a lot of time to topic selection while making sure that you have chosen definite, politics oriented and correctly structured central thesis statement. (my-thesis.net)
I have been following the slow and arduous acceptance of author Michael Fumento's central thesis presented in his book The Myth of Heterosexual AIDS and in his series of articles in The New Republic and in Commentary with great interest... So I was extremely pleased to read your editorial position concerning AIDS. (firstthings.com)