Science doesn't explain everything that exists: ask the best scientist in the world to explain God (if he doesn't believe you, ask him where everything comes from and who runs the universal mechanics of how things work), a mother's love, changes in the water molecule through the energy patterns it is subjected to, presentiments, spirits, etc. You'll see how he can get bogged down and end up saying that “none of this is science”. In other words, much of what surrounds us simply escapes the “necessity” of scientific scrutiny, but it doesn't lose its usefulness for that reason.
It doesn't explain why:
Not everything can be explained by current scientific knowledge, which may (and indeed must) be too late to understand many phenomena. Historically, what were considered “absolute truths” at one time were seen as wrong and even absurd decades or centuries later, when scientific knowledge evolved, matured and rectified what was in force.
Economic interests mean that many people want everything to stay as it is. For example, those who have invested a fortune in a mammography machine don't want the reliability and suitability of mammography to be questioned. And does the oil industry really want research, development and use of alternative fuels to increase? As for scientific studies, will what “doesn't make money” be as extensively researched, funded and reliably disseminated as what does? Is there more research into healthy lifestyle habits or medicines to treat illnesses? On prevention, cure or treatment? A cured patient is no longer a client of the disease industry. Not to mention unreliable studies, with results manipulated or disseminated in such a way as to lead to specific conclusions, conflicts of interest, etc.
The “security” of the “safe haven” that the traditional provides: those who choose to simply accept and propagate the traditional as it is, without question, always find a majority like this and end up feeling comfortable in “being accepted” and not being attacked. What's more, if things don't evolve, those who stick with the “traditional” experience the comfort of being able to continue using in their theory and daily practice what they learned at university, “without taking away or putting back” (after all, studying, updating and therefore changing “for what”? It's hard work) for decades.
Multifactorial environments: the vast majority of studies draw conclusions about very specific situations that can rarely be reproduced in human beings in their daily lives, subjected to stress, multiple external factors, lifestyle habits, disorders and pre-existing diseases. For example, a study which says that vitamin E is dangerous for X and “doesn't work” in Y rarely takes into account the pre-existing nutritional status of those involved, what their diet is like, the balance with other vitamins and antioxidants, the level of stress each has been subjected to (yes, this greatly affects the consumption of reserves, including vitamins), which vitamin E has been used (there are several forms, with differences in some of their actions and interactions).
If current science only seems to believe what it has “evidence to prove”, I wonder about the value of accumulated experience. In medicine, there is a lot of talk about Evidence-Based Medicine, but curiously, in this field, very little value is placed on accumulated practical experience or the existence of even thousands of successful cases of something, if there are no blessed, indexed and attested “double-blind randomized placebo-controlled studies”, etc. For example, if a substance that has been successfully used for thousands of years has no “new” studies proving what is already known, does it lose its useful status and become mysticism? No longer useful? We're living the paradox of a science that seems to want to explain everything, but is increasingly dismissive of anything that contradicts it. Is this a problem of self-esteem or just an attempt to hide the basics (that science doesn't explain everything in essence, at least not in the current mold)? The great Dr. Alexandre Feldman discusses this well here: https://www.enxaqueca.com.br/bom-senso-versus-medicina-baseada-em-evidencias/
In short, the question seems to me to be more one of common sense: our current application of science should be less arrogant and understand the obvious, which still doesn't explain everything, but learn to have the humility (also to face it!) to constantly evolve (accepting more and rejecting less, improving its own flaws) and truly incorporate this necessary status of “constant evolution”. Maybe one day I'll be able to explain it. And that if not everything seems to have evidence, perhaps the problem lies in what is considered and accepted as evidence and not in the lack itself - by the way, who stipulated what is acceptable as evidence? And are those responsible for this totally reliable, up-to-date and free of prejudice, with a vision of the future and the constant need for evolution? I hope so... For the sake of science and all of us who depend on it. Until then, maybe, just maybe, not everything that is useful will also be considered scientific. But it will still have value. It's accepted by those who want it, when time and practice attest to it.
An important warning (before some people start complaining): I'm not against relying on scientific studies, on solid evidence to base the majority of clinical practice, and I do this routinely in most of what I post and use/indicate in the office. I recommend that as much of our health practice as possible be based on evidence. I am against abuse, which I have detailed well and clearly in the text above.
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