The following is a chapter in a story I'm writing to promote the Pro-Truth Pledge, Earthlings: People of the Dawn. There aren't any major spoilers in it so it kind of works as a standalone short story as well. It explains some of the major flaws of contemporary science.
Ji-Yu strode into the classroom where her students were already waiting for her.
“Hello Sensei,” said the class, sullenly. All of them were ancients who had once been amateur scientists.
“Welcome to the tutorial on basic contemporary science. For many of you, the reason you are here is because, despite what you were told on Ancient Earth, your skills are woefully inadequate for success in your discipline.”
“That's not true! We were all experts in our fields!” shouted one of the students without raising his hand.
“Relative to most everyone else who lived back then, yes, you were experts,” said Ji-Yu, cooly. “But reality does not grade on a curve, and neither do I. It doesn’t matter who does better or worse. What matters are results. The results of Ancient Science are impressive, given its shortcomings. But in the end, Ancient Science wasn’t fast or strict enough to ensure the survival of the human species.”
“Then how are any of us still alive?” another one of the students demanded. “Divine Intervention? Aliens? Is there some crazy pseudo-scientific explanation you have in mind?”
“Hardly,” said Ji-Yu. “Listen well, all of you. The answer to your question requires some background knowledge.”
“A long time ago, long before even we ancients who are still alive today, there was a man named Aristotle (I'm sure you've heard of him before), who believed that it was possible to uncover the secrets of the Universe only by thinking. He believed that to judge things merely by their appearance was a poor way to arrive at truth and would only fool you in the end -- that you couldn't trust how something looked, you needed to rely only on thought. Obvious nonsense, yes?
“Then one day, some people thought of the opposite idea: that it was possible to uncover the secrets of the Universe only by their appearance. They believed that to actually think about things was an empty pursuit and would only fool you in the end -- that you couldn't trust your thoughts, you needed to rely only on what you could see and touch.”
Ji-Yu gazed at them all sternly. “Reversed stupidity is not intelligence. The dumbest person in the Universe can say ‘The Sun is Shining’ but that doesn't mean it's dark out. It should be extremely obvious common sense that uncovering the secrets of the Universe requires you to not only look, but to actually use your brain as well. But most of Ancient Humanity lacked that common sense because they were not trained to use it. Ancient Science was built around the assumption that scientists are too stupid and self-deceiving to be able to trust their own brains to process evidence. It didn’t even occur to ancient scientists that they could develop training programs which could teach them how to overcome biases and avoid cognitive errors.
“Furthermore, Ancient Science allowed its practitioners to avoid updating their own theories with evidence for as long as they liked, so long as they updated eventually. There was an old saying that I’m sure you’ve heard before that Science advances one funeral at a time. Not one definitive experiment at a time. One funeral at a time. Ancient Science didn’t advance because its more experienced practitioners updated or replaced their old falsified theories, but rather because its most experienced practitioners died, and their outdated theories with them.
“Scientific consensus was still the most reliable indicator of whether something was true or not, but that wasn’t much of an accomplishment -- since it would only form after scientists gathered enough overwhelming evidence to beat themselves over the head with. Ancient Science was much more accurate and reliable than other sources which existed at the time, but it was still unimaginably slow on the uptake. It took them decades to solve mysteries that today’s scientists could solve in months or even days!
“That is beyond pathetic, and it's practically a miracle that such an inadequate institution was able to support the development of a technological civilization in the first place.”
The students stared at their instructor in astonishment as she continued her lecture.
“Imagine that there was a cliff, and you hypothesized that if you walked off that cliff, you wouldn't fall to your death. A scientist of Ancient Earth, perfectly obeying the laws of science as they understood it back then, would have been permitted to assign a non-negligible subjective probability to your not falling to your death if you step off the cliff, prior to conducting the experiment by watching what happens when you step off. Yes, falling to one’s death is what happened when others tried it, but how would they know that it would happen to you too when you tried it? Technically, this particular hypothesis has never been tested. That scientist won't know for absolute certain if you will fall to your death until you actually hit the ground, since until then they don't have data from a definitive experiment saying that you would.
“If you still doubt that you would have survived walking off a cliff on Ancient Earth without a parachute or anything similar, Ancient Science does not provide sufficient technical justification for your doubts to hold weight, because you haven't done the experiment yet.
“But Bayesian Probability theory does provide sufficient technical justification. In Bayesian Probability, every change in the probability assigned to a hypothesis requires some amount of evidence. The bigger the change, the more evidence required. To justifiably have 100% certainty in a hypothesis, you need infinite evidence. This is the case even for hypotheses with as extremely high a probability such as ‘If I walk off that cliff I'll fall to my death’
“ But the amount of evidence needed to be 99.99999% certain of a hypothesis is much smaller than infinite evidence. And because our brains don't intuitively grasp differences of probabilities that small, they are rounded off. It's significantly less likely that two plus two equals three than that Santa Claus exists, but the amount of evidence against both hypotheses is so great that our brains cannot intuitively tell the difference. Any amount of subjective probability our brains are capable of assigning to hypotheses as unlikely as that would be too large, so we simply don’t assign any subjective probability to them.
“You don't need to be infinitely certain that you will fall to your death if you step off the cliff to avoid stepping off of it. You just need to be certain enough. You don't need a definitive experiment for that. If you already know that other humans have about the same amount of resilience to impacts of that strength, that the cliff probably isn't significantly changing its height any time soon, that the ground below the cliff probably isn't significantly changing its hardness any time soon, and that the law of gravity still applies, then just check to see if other people who’ve fallen from similar heights onto a similar surface without a parachute or other such device survived their falls and you’re done. You have enough evidence to be extremely certain, though not infinitely so. It’s sufficient to make a decision.”
Another one of the students raised her hand.
“And before you ask,” said Ji-Yu. “By ‘subjective probability’, I mean how much you expect a hypothesis to be true or false given the evidence available. You can feel how much subjective probability you’ve assigned to a hypothesis by imagining hypothetical future evidence which confirms or falsifies that hypothesis and asking yourself how surprised or unsurprised you would be by that evidence.”
The student put her hand down.
“The reason we survived was not because the ancient institution of Science finally got its act together and began to reach its full potential,” said Ji-Yu. “The reason we survived was because some people who studied Bayesian Probability outside of conventional academic spaces recognized the scientific method as it was understood at the time for what it really was: an approximation of Bayesian probabilistic reasoning. They used findings in the cognitive sciences to improve their thinking skills, and applied their understanding of Bayesian Probability theory to help solve important and neglected scientific and technical problems. To this day they are remembered as some of the greatest heroes of Ancient Earth. That is why we are still alive.”
The ancients just sat there, speechless.
“Your final exam in this class, which you will likely take at some point later this year, is to rediscover the correct theory of quantum gravity given germinal background knowledge. You’ll be graded on speed as well as accuracy. Additionally, you’ll be keeping a research log throughout the exam, where you’ll write down your entire procedure to rediscover the theory.
Over the coming months I will teach you the skills you will need to successfully pass that exam. I look forward to working with you.”
Ji-Yu bowed. “Class dismissed.”
The ancients fled the classroom as if their lives depended on it. They felt as if their final exam was a great beast which would, sometime within the coming year, swallow them whole.
The first-week panic had begun.
Also this scene was largely inspired by the following blog posts: