The beginning of wisdom is, ‘I do not know.’ [gestures toward the “hole in space” on the viewscreen] I do not know what that is.
– Lt. Cmdr. Data, “Where Silence Has Lease“
“I don’t know” is a phrase that probably should get more mileage. When used appropriately, it’s humble. It’s honest. It’s open. The universe is a big place with lots of tiny details, so it shouldn’t be a surprise that there is still much that we don’t know as a species, let alone as individuals. Being aware of that ignorance inspires both caution and curiosity, virtues of science. We can devise hypotheses to explain unknown phenomena, but a scientifically minded person doesn’t jump to the conclusion that his hypothesis is true without carefully testing it. Sincerely admitting ignorance typically means being open to entertaining new ideas as well. Those ideas still have to be tested before they’re accepted as knowledge, of course.
There’s an annoying idea I’ve encountered with various pseudoscience trolls, quacks, and especially with Creationists. They treat any admission of ignorance from their opponents as a victory for their ideas. It doesn’t work that way. For an example, let’s say a particular type of cancer has no known effective treatment. Just because the scientific community doesn’t have an answer doesn’t mean that we should accept a quack’s answer, especially if that answer wasn’t informed by scientific research into its plausibility.
Science is cautious by nature. The world is a complicated place, and there’s always the possibility of discovering new nuances and exceptions to the rules we’re familiar with. We can’t have absolute certainty in what we do know because of our human limitations. The language of scientists typically reflects this, since they will mention nuances, limitations, exceptions, and uncertainty from simple probability.
Pseudoscience doesn’t like humility or measured confidence, often characterizing it was “weak” language. Statements of absolute certainty and absolute rules are much more marketing friendly and easier to fit into a slogan. Religion is quite aware of this and sets up gods and holy books as absolute authorities with circular reasoning. Quacks and pseudoscientists often follow suit and enshrine their gurus and particularly the original creator and his texts. In either case, they often implicitly or explicitly claim they have all the answers in a convenient package. This tends to lead to stagnation. The scientific community knows that it doesn’t know everything. If they did, science would stop.
I think treating “I don’t know” as a concession taps on an unhealthy obsession with completeness and perfection that overrides the healthy desire to know the truth. One problem with many religious, supernatural, and pseudoscientific ideas is that they can explain anything. If you’re sympathetic to those sorts of hypotheses, that’s not a strength. If an idea can explain anything, that’s actually a big problem: It can explain things that don’t exist just as readily as those that do. It can explain failures and success equally. It essentially means that we can’t use it to make predictions to verify its accuracy. We can’t use it to make predictions or decisions. It’s ‘heads I win, tails you lose.’ Such ideas are essentially a way to deceive yourself with the comforting illusion of understanding without the practical benefits of real understanding.
There’s another idea that any answer is better than none. This is simply not true. Actions based on an incorrect idea can be more harmful than inaction. They can waste resources better spent elsewhere. I can understand desperation in the face of death and the desire to go down fighting, but that doesn’t mean I should rhetorically support those who can exploit desperate people just because I don’t know the true answer.