At any rate, philosophically speaking, science is the study of the material, which includes matter and energy, while metaphysics is speculation about the material, which can include more than matter or energy.
A marked difference between the two did not really become apparent until about the time of Isaac Newton. Leading up to his time, scientists began to divorce themselves from clerical control and set up independent "review" bodies of their own, such as the Royal Academy in Britain. This "divorce" was not intentional, per se. What happened was that scientists gradually saw themselves as having a "mission" separate from spirituality; at the same time, the religious upheavals of the Reformation forced the churches to focus solely on spiritual and (in some cases) political needs; the two "factions" simply grew apart, of their own accord.
Since then, of course, science and religion have grown as far apart as one can imagine. Many people are under the mistaken belief that science is the "opposite" of religion. This is not so. Rather, they are just two different things.
After science diverged from religion, it became centered on matter and energy; concerns such as the nature of spirit were dropped, only to become part of theology. Metaphysics is now frequently confused with religion; while all religion is metaphysics, not all metaphysics is religion.
Metaphysics, on the other hand, has no method of investigation. Furthermore, observation generally has no place in metaphysics (since the metaphysical cannot usually be observed). There is literally no way to verify any given metaphysical concept, and no way to refine, according to a disciplined procedure, previous metaphysical concepts. Metaphysical ideas are supported solely by logic and rhetoric.
Logic and rhetoric are not bad things, by themselves, nor are they unscientific — scientists use logic as part of the scientific method, and they use rhetoric in order to explain their findings. The problem is that they do not provide a very solid foundation for knowledge, all by themselves; if one is a clever enough logician and rhetor, one can make the most preposterous ideas seem reasonable, regardless of their merit. Logic and rhetoric are indispensible for learning, however, they are just the "medium" for conveying and absorbing knowledge. Other factors must come into play as well, if one is to acquire bona fide knowledge.
A rather striking — and obvious — manifestation of this tendency, lies in the vast number of "urban legends" that get passed around. At the moment, the Internet seems to be the chief impetus for most urban legend, however, unbelievable tales are swapped over the water cooler at work, over the dinner table at home, or over drinks at the bar. The obvious preposterousness of most of these tales is overlooked, in favor of their dramatic flair. Furthermore, since these tales usually come from "trusted" sources (friends, spouses, co-workers, etc.), most people don't even think to question them.
Some of these "urban legends" consume even those who ought to know better. Journalist and J.F.K. advisor Pierre Salinger, for example, was fooled by hoaxed French intelligence reports claiming that TWA flight 800 was shot down by a Navy missile. He is a smart man, who had the means to investigate these "reports," and presumably he did so; yet he believed, erroneously, and ended up with egg on his face.
Frequently, people believe things simply because they see them on television or read them in print. They assume that whoever would go to the effort of broadcasting or publishing something, would have looked into it, and was sure of it. Well, obviously, this is not a valid assumption! In fact, most people know this — however, they do not often act accordingly.
It's very difficult to present something scientific in a manner that will hold people's attention. For example, I saw a documentary on Atlantis recently; while it did offer a skeptical viewpoint, and even concluded that the rather mundane Thera/Santorini theory was probably behind it, most of the documentary was taken up with spinning tales of Atlantis, what life might have been like there, and so on. This is, of course, the only way that the documentary would have worked. To show an exhaustive scholarly explanation of the Thera/Santorini theory, and leave out the rest of the more dramatic — if unsubstantiated — material, would have been very dry and boring, indeed.
One area in which metaphysics and science blend, with dangerous (and possibly lethal!) results, is in so-called "alternative medicine." This is a misnomer, as most "alternative medicine" isn't really medicine at all. Medicine is a scientific discipline, in which diagnoses and remedies are applied, tested, revised, and so on, according to rigorous standards. It is both remedial, meaning that it provides remedies for ills, and investigational, meaning that it looks into the causes of diseases and the mechanisms by which remedies work. Alternative medicine uses no such standards, and while it is remedial, it is in no way investigational. Moreover, while medicine is regulated, using remedies which have been clinically proven safe and effective, "alternative medicine" is virtually unregulated; its remedies are almost entirely unproven, either in effectiveness or safety.
These forms of medicine are metaphysical, in that they posit that the body is made up of five elements (water, air, fire, metal, and wood) and that there is a life energy, or qi (chi) running through the body in meridians or energy-veins. Just as with the spinal subluxations of chiropractic, no one has ever seen a qi meridian — nor can anyone explain how sticking pins in a meridian does anything of consequence. Nor can anyone explain how ingesting ginseng extract gets rid of excessive "wood" in the body.
Perhaps ... but consider that many people would probably be better-served by conventional medicine, a scientific discipline which continually revises itself, as research allows.
Astrology continued to be used, ever since, continually revised and expanded upon by its practitioners. The few scholars who could master the necessary calculations, made very good money as astrologers. For some, such as Johannes Kepler, it was the only way they could make a living; no one in Kepler's day had much reason to hire a mathematician — but plenty of wealthy folks wanted to know their futures.
The fundamental problem with astrology is, of course, that no one can explain any mechanism by which heavenly bodies have any effect on individuals. Moreover, all efforts to prove the veracity of astrology, scientifically, have failed miserably. While many people believe in astrology, this belief does not grant it any truth.
Meditation, however, has no verifiable basis. While it certainly can have a calming effect — halting everything to sit quietly for a while will, by definition, do that! — its effects on health are questionable. As for gaining "insights," where do they come from? A lot of people talk about "the Higher Self," but what is that? A soul, or spirit? If so, what is a soul or spirit? What is it made of, and how does it connect to the body? Are you dizzy yet, trying to figure it out?
As should be clear, now, the presumed metaphysics behind meditation is extremely fuzzy. Even so, too many people place their faith it, and trust their health to it.
What most people do not realize is that those commercials are carefully scripted; the "callers" and the putative psychics, are all actors. These psychics can only do what are known as "cold readings," which is a modern version of old-fashioned "parlor-trick" mind-reading. These psychics cannot point to any mechanism by which they can see the future, or even know anything about someone, especially through a telephone connection. When psychics are tested under controlled, scientific conditions, they fail miserably.
Perhaps most egregious of all, are the so-called mediums, those psychics who claim to speak with the dead. They claim to be able to speak to their victims' late loved ones, offering comforting messages. What most people do not know is that they use cold-reading techniques. Additionally, those mediums who work on television, edit their programs so as to leave out their numerous "misses" or mistakes, and include only their coincidental "hits," or correct statements. And even misses are characterized as something the person in the audience was unaware of, or would come to pass in the future — no medium ever admits to a mistake! Finally, most people who admire these mediums, are unfazed by the fact that the dead who speak to them, rarely have any concrete messages for their survivors; you never hear, for example, "I buried a jar of silver coins next to the shed." The message from those who have "passed over" is always amorphous and indefinite, such as, "I'm OK here."
These mediums prey on the most vulnerable people of all, that is, the bereaved. To make one's living on the grief of others, is reprehensible — especially in light of the fact that these mediums cannot really offer any true help. These people really ought to be in psychotherapy (of the conventional kind) or in a bereavement support group — not in a television studio watching a charlatan doing cold-readings on an audience!
At any rate, no one has been able to explain how psychics can "see" the future, or heal over long distances, or know if a potential mate is "the right one." There is no scientific basis for any psychics' claims.
Accordingly, many authors have penned whole volumes, explaining how to go about finding one's "soul mate" (or other similar term). Their underlying assumption, of course, is that, for each person, there is one other person "out there" who is his or her soul mate. Souls are continually reincarnated, these authors claim, and they strive to find each other, within each lifetime.
Of course, none of these people can say what a "soul" is. Nor, assuming that they exist, can they say how it is that souls reincarnate. Nor, even assuming that souls exist and reincarnate, can they explain how souls manage to reincarnate so as to be able to find each other.
This is not the case, though. Near-death experiences (NDE's) in the United States tend to be similar, those of Europeans tend to be similar, those from the Middle East tend to be similar, etc. But there are differences between the NDE's of these cultures.
The cultural aspects of NDE's imply that they are the result of a personal interpretation of some sort of experience. Whether or not this "experience" is caused externally of the person, is unknown. But, neurologists are able to offer a likely explanation: that these folks have suffered from anoxia, or oxygen deprivation to the brain, which in turn has neurological effects, that these people interpret according to their prevailing culture.
Scientifically speaking, we are still unsure of the underlying cause of the NDE phenomenon. But one thing we can be sure of, is that it does not, by any means, "prove" that there is life after death. If anything, science suggests that this is probably not the case.
Clearly there is a phenomenon occurring — but is it extraterrestrial? Or is it far more earthly, or even human in origin? For all the reports that have been made, for all the people who've claimed to have been "abducted" and experimented on by alien UFO passengers, we have an appalling lack of physical evidence that anything is going on.
"That's because the Government is covering it up," some UFO enthusiasts claim. "There's a conspiracy to keep us from knowing. They don't want to cause a worldwide panic." OK, fine, I admit it: most western governments might possibly participate in a conspiracy like this (though I think it quite unlikely).
But ... can that conspiracy be so rock-solid as to never allow any evidence to be "leaked?" Government agencies deal with the possibility of information leaks, every day, even in the strictly-regimented military. Inevitably, someone will disclose something here, or give away something there, whether intentionally or inadvertently. There is simply no way that a "conspiracy" of this worldwide scope could remain in place for over five decades. It's absurd!
Explanations for how aliens do what they do, call upon metaphysics, and misunderstandings about science. For example: Aliens are said to be able to "draw" abduction victims through walls (usually of their bedrooms). They do this, many say, by taking advantage of the vast "space" between the elementary particles that make up the person's body and the walls, as pointed out by quantum mechanics. The aliens literally "slip" their victims, and themselves, through this intra-atomic space.
The problem with this, of course, is that, in order for an atom to remain stable, the intra-atomic space must be there! If an external particle got between an atom's nucleus and electrons, depending on what it is, it might cause the atom to fly apart (which would be tantamount to a thermonuclear explosion)! Quantum mechanics not only tells us that space is there — it tells us that stability requires it to remain empty!
Similarly, the aliens' ability to surpass the speed of light is explained as "folding of space" which, supposedly, Einstein's relativity allows for. Again, however, this is a misreading of science. Einstein showed how space could be considered "warped," yes, but to warp space enough to go faster than the speed of light, results in a "singularity" which causes relativity to fail. By definition, relativity cannot possibly tell us how to go faster than the speed of light, because the mathematics of relativity doesn't allow it.
As I said, there is no physical evidence that extraterrestrial explorers have visited our planet. None. Films and photos are easily faked — especially with today's technology, but even old-fashioned "double exposures" can look convincing. Some people claim to have had alien implants, but they either disappear (must have been the Government Conspiracy!), or turn out to be mundane plastic or metal parts.
The only real "evidence" is eyewitness testimony of UFO sightings and alleged alien-abduction stories. Many of these things are highly suspect, however. Even "reliable witnesses" can mistake distant lights for UFO's, and any abduction stories are easily explained as episodes of apophenia or "night terrors" caused by many factors.
A lot of this stuff is put forth by — dare I say it? — swindlers, preying on the public's ignorance, using fast-talk to get people to go along with their ideas. Often, they portray themselves as "victims" of the "scientific establishment," who have a good deal to offer the world, if only they weren't plagued by scientists, corporations, etc. who are trying to keep them silent, because they profit by doing so.
For example: Those who sell alternatives to pharmaceuticals for ADD/ADHD children, often use this ploy. "The big pharmaceutical companies don't want you to know," they claim, "for they profit by forcing drugs on your kids." This is ridiculous! Pharmaceutical companies don't make a lot from ADD drugs, which are stimulants that they've manufactured since the 1940's. There are no patents remaining on them, and very little profit margin. Kids may be "overprescribed" — the jury is still out on that — but not because of pharmaceutical companies' profit motive.
My advice is to keep an eye out for things which are either not very believable, or which are ill-defined or for which no explanation is offered. That, perhaps, is the key to it all: Explanation! Whatever you decide to look into, demand an explanation for how it works, why it works, etc. That explanation should be sound, logical, reasonable, and should never ever resort to terms such as "indetectable," "unseen," or anything of that sort.
Unfortunately, schools generally do not teach this. So, parents, you will have to do it.