Dr. Bledsoe is angry with the narrator for bringing Norton to visit Jim Trueblood, a Black man living in the former slave shacks near the college.
Trueblood impregnated his daughter and speaks openly about it. Bledsoe, modeled on Booker T. Washington, the accommodationist founder of the Tuskegee Institute, the model for the narrator's college, believes that in doing this, the narrator threatened the financial foundations of the college. He can't understand how the narrator could fail to understand the fundamental principle of Black survival that you must lie to white people and give them what they want to believe. Instead, the narrator challenged the carefully crafted narrative of a docile and uplifted Black population that would do good and stay in a subservient role by inserting Trueblood into the picture.
More to the point, Dr. Bledsoe has staked his future fortunes on a narrow view of his own personal power that makes it dependent on manipulating white people. Bledsoe doesn't challenge the second-class citizenship of Black people or the racist society he lives in, but opportunistically does everything he can to wring what power he can out of accommodating himself to this reality, which he believes cannot be changed. He is furious at the narrator for not "getting with" this system.
Through Dr. Bledsoe, Ellison paints a devastating portrait of Booker T. Washington, a Black leader who was seen by many as being too willing to cater to white desires at the expense of Black dignity and rights.