Also, things that are white can be judged by the amount of light they reflect or scatter as a percentage, independent of the source of illumination. For instance, among familiar objects, a common white ceramic bathroom tile comes pretty close to pure white.

Also, a thing can't be "whiter than white" in nature unless it's fluorescent. So it represents a kind of limiting case that people can agree upon.

Accountants and lawyers effectively controlled their customers. You can't use accounting or legal work for business purposes without those things coming from licensed practitioners. And they have no other use than to work with regulatory agencies (loosely speaking such as courts, IRS, etc).

If you lock down software development too hard, people will write their own. It's easier to hack something together that solves a specific problem than to write general purpose software that can be sold. And eventually the licensed programmers will break their own rules, for instance by using un-approved computers, languages, and development tools, in order to compete with software smuggled in from overseas.

At my workplace, the earliest programmers were a combination of self-taught and people with real CS degrees. The CS people wrote the OS and languages for an in house minicomputer. The apps were written by people with app experience, mostly scientists. And there were a few odd characters like the secretary who learned programming because it was quicker to fix bugs herself than get clarification from the engineers.

Before that, there was science. Although the rules were loosely defined, scientists were expected to provide enough detail in their papers for someone else to replicate their work. That's where I learned about open design, before I learned to program.

Into the modern age, when "code" became part of electronics projects, the magazines printed source code listings, and later required authors to provide their code for an online repository. I published a couple of those articles back in the day.

My mom was a public high school teacher. When I described the conditions of working as an adjunct, her knee jerk reaction was: "That's why teachers have a union."

So its existence is often largely treated as an empirical rule of thumb rather than having a specific physical cause.

The other thing to note is that the noise plot in a dataset is probably a curve fit.

Disclosure: I was one of those teachers for a semester, many years ago.

Also, teacher pay is not as rigid as it seems. In my state, the good teachers advance by moving to better paying districts. Very few teachers stay in rural districts for more than a year or two.

Not negotiating is also an option, and not something to feel weird or anxious about.

Worst case scenario. Against my best instincts, I opened my door to a salesman. He wanted to sell me new Internet service. I said No. He asked why. I thanked him for his time and closed the door. He's a trained hustler, and I'm a terrible negotiator. Nothing good would ever come of negotiating with him. I can make a perfectly good estimate of the probability of us finding a mutually acceptable middle ground... zero.

People will constantly ask you for things that are not in your best interest at all. They're betting on a chance that you will feel obligated to give them something. They can learn that sometimes people will say No without giving a satisfactory reason. They have probably already learned it.

Sure, the reaction time is slower. You learn to think ahead.

Nothing is optimal. The tenements that my kids lived in as students had gas stoves and zero ventilation. That couldn't have been a good idea.

Our latest stove is induction, made by LG, with control knobs. I love it. Best thing is it's easier to keep clean. I'm learning to be more reactive about turning the heat up and down, just because I can. Maybe I'll discover what I've been missing all these years.

Julia Child wrote that a home cook doesn't have to be a chef.

True but maybe a blessing in disguise. As a shy college kid once (although not with any real disability), being forced to get up in front of people helped me get over it. And I was 10x better after a semester of teaching during a break in my career.