I think it was easier when I just saw it as peer pressure. In fact, I think the teenage maelstrom of awful social bullshit made it too easy for me to hope that maybe I wasn't the problem. Then everyone grew up, people got a lot nicer, and I had to face up to the fact that I was constantly screwing up social situations that should be very easy for everyone involved. Encountering someone friendly at a social event who wants to talk to me and is curious about where I'm from and what I do. Seeing someone who feels awkward and out of place in a situation where the right words from me could put them at ease and make them feel welcome. After talking to me these people can feel less comfortable than they did before, and not eager for a second encounter. A poor social performance can undermine good feelings and compound bad ones. When I was a kid and was a misfit for a lot of reasons, many of them positive, I could frame it as simply "not fitting in," but now I have every advantage and every opportunity and I realize I still have to be right on top of my game to avoid bringing bad feelings into the world for other people.
Why can't I do what they can? Without a diagnosis, the answer to that question can be "because I am a failure as a human being", leading to erosion of self-worth. But being able to answer "because I have a handicap" (due to the mental condition) helps think more constructively about how to work around the handicap, rather than just expect to be able to overcome it.
In this thread, there an insightful comment that reads: it's like realizing that you are short... after decades of being told that the only reason you can't reach as high as most people is because you are lazy.
When you said "people often use it as an excuse to not work towards improving themselves", that is exactly what the author of the comment meant by "being told [that they're] lazy". No matter how much a short person "work[s] towards improving themselves", they will not get taller. They instead find ways to work around the issue, like carrying stepladders with them.
Keep in mind, that if we had never invented glasses, a huge swath of the world's population would be considered to be handicapped. And the ones that weren't, who have only experienced poor eyesight due to dust or tears in their eyes (temporary conditions, just like feeling sad would be in comparison to depression), they could very well share your attitude, and insist that people just need to "look harder".
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> In this thread, there an insightful comment that reads: it's like realizing that you are short... after decades of being told that the only reason you can't reach as high as most people is because you are lazy.
> When you said "people often use it as an excuse to not work towards improving themselves", that is exactly what the author of the comment meant by "being told [that they're] lazy". No matter how much a short person "work[s] towards improving themselves", they will not get taller. They instead find ways to work around the issue, like carrying stepladders with them.
Or summarized more concisely: One needs a diagnosis because other people are simply a##holes.
However, I was thinking more about people labelling themselves internally, which is what the linked article focuses on. In that case, thinking of one's self as handicapped can be beneficial, which is what the article presents example of.
Since there is a medical professional involved in the diagnosis, they should be able to steer the patient towards the mindset that would be most beneficial for them, given each individual's circumstances. Repeated sessions work towards helping psychiatrists figure out, as you say, "which exact behaviours can be attributed to autism and which to personal development", and they can advise accordingly.
Minor nitpick: you said "psychologists", when "psychiatrists" would be more accurate. The latter are medical professionals who have gone through at least 14 years of study and practice, including a residency at a hospital, and they are the ones who are able to diagnose and prescribe medications. They are doctors, in the full sense of that word. Psychologists are not medical professionals (but that doesn't mean they're not useful).
I consider the mistake rather in the assumption that there is free will. If you simply get free of the dogma that there is free will, something like "fault" simply does not even make sense to formulate anymore. EDIT: And you surely already found out beforehand on your own that you are different.
With a professional saying that they have a condition that's beyond their control, and labeling it for them, it helps them say "I'm different, but it's not my fault."
It shouldn't matter. Be different if you want to. Don't give in to peer pressure.
But that just isn't how people work. Most people actively want to be liked and to fit it, even if it's not in their nature to do it effortlessly. And it bothers them when they aren't doing it well.