References to an External World

I have wanted to write a post about radical constructivists' making references to the external world for a while now.

Jules: Jules, a radical constructivist, references his C- grade and Allison. If his reality is constructed, then why does it really matter if Allison gave him a C-? Why does the grade even exist in his reality? If, in his experience, he is an A+ student, then why is he letting this C- get to him? He is trying to convince Allison that he is right and she is wrong about her evaluation of him, which is contradictory to the beliefs of radical constructivism.

Von Glaserfeld: I found it a little humorous that in von Glaserfeld's "Introduction to Radical Constructivism", he lists references at the end. This seems contradictory to the principles of radical constructivism. Von Glaserfeld has not experienced what the people he cites have experienced; how does he know he is accurately referencing them? What if he completely misinterpreted what they wrote and is drawing an incorrect conclusion about their work?

Haans interacts with Allison and Russell, and references Jules' letter. These things may seem nit-picky, but I really don't understand how a radical constructivist can never reference an external world.

Constructivism and Mental Illness

According to radical constructivism, there is no objective reality or truth that we as humans can know about. Mental illnesses, often diagnosed due to "abnormal behavior", are relying on the assumption that there is a "normal" and objective way to behave, think, and feel. First of all, if all we can ever know is how we ourselves feel, how can we medicalize the way somebody else feels? A radical constructivist would say that we cannot tell a delusional or hallucinating person that what they are experiencing is not real; a doctor/medical professional has only his or her own experience to pit against the patient's.

Even a medical professional cannot know the way most people feel, or the "normal" way to feel. They can only know the way they feel. So, how can they determine if somebody's mental state is abnormal? How do they know that their own state isn't abnormal? Are medical professionals judging what is normal based on what they experience? Furthermore, what is considered abnormal, and is it socially constructed?

(Another) Response to Becky's Post, "A Radical Construction of People"

Although I already responded to Becky's post about Constructing people, I have been thinking about it more and I want to respond again. Becky said in her post that you couldn't really know a person until you experience them yourself; you can't trust other people's judgements and opinions. According to the radical constructivist, you cannot know anything outside of your own experience. However, what if you trust another person's judgement enough to take their word as fact (or almost fact)? If a radical constructivist knows somebody who always seems to interpret the world the same way you do, can he or she rely on that person for the "truth" (or their version of the truth that tends to match up with his/hers)? Can a radical constructivist rely on other people for information?