Kierkegaard wants us to understand that while we might not have much choice in how we feel at a given time, we have control over and responsibility for the way we relate ourselves to those feelings.
Marino, Gordon. The Existentialist's Survival Guide (p. 75). HarperOne. Kindle Edition.
Bias is tautological. It says 'this person likes this thing because this person has a higher tendency to like this thing because they are this kind of person to like this thing because...' Bias does not touch internal motivations, what structures or generates the bias, etc. In other words, bias is a symptom that impels us to search for its origin or cause, not a cause or origin for anything. Now we're back in psychoanalytic territory.
A simple example: a patient criticizes me for being incompetent, offering no help, etc. I feel I have worked hard to try and understand and help this patient and feel a tinge of annoyance, or building frustration. All of a sudden without much thought I am running through in my head all the ways I have helped the patient and why the patient is wrong. Oops. I catch myself. The patient feels me as bad and I have just tried to avoid the transference. I notice this and say aloud, with meaning and feeling, 'I've really let you down. What should I have done differently?' Here it is likely the patient transferred onto me an early experience with a caretaker. But whereas the caretaker - as parents often do - was most likely unable or unwilling to accept criticism and ask for feedback, probably doing the opposite by attacking the child or becoming overly defensive, I give the patient a new experience that allows new thoughts and feelings to come to light. Patient: 'wow, no one has ever said that to me before...'
The art needed to be submerged in the acid bath of the hidden personality and then reconstituted, which is what William Gass does without parallel.