His site sells generally decent-specification instruments that can also be used for scientific and industrial purposes. The prices are exceptionally reasonable, he’s not gouging anybody. Most of the products are completely mundane – weather station stuff, pH meters, sound meters and so forth.

Due to “Ghost Hunter”-type TV shows, many people were looking for instruments like the ones they saw being (ab)used in the shows. This guy already was selling most of them  for other purposes. Was he supposed to refuse to sell unless customers swore an oath of allegiance to CSICOP or something? As far as I can tell there are no claims on the site about detecting ghosts – the closest is on the “EMF Meters” page are some  bundle deals with voice recorders and infrared thermometers.

The people who buy these EMF meters are going to go out and measure things and will have to interpret those measurements. Some will thus start getting into more regular areas of science as they are exposed to the real invisible world of EM fields. The others would be able to delude themselves about things that go bump in the night with or without the instruments.

And, no, the device that is determining whether you are doing more than the speed limit is called a “cop”.  A machine can’t do that; it can’t measure intangibles like the law, only physical properties like velocity.

They laughed at Marie Curie for saying her photographic plates could detect “radiation”. Women, huh? Of course, they also laughed at Bozo the Clown. I’m not saying that this guy is closer to the Curie end of the Curie/Bozo spectrum. I’m just arguing a general principal.

Not quite. If someone says that “heaven” is a literal place that conforms to the same laws of physics with which we’re familiar, and it exists as a tetrahedron 100 miles on each face, floating 100 feet over the intersection of latitude 38 and longitude 122, we CAN indeed find proof of its existence or nonexistence.

By the same measure, we can determine that the “heavens” claimed by many religions are simply impossible to exist unless one wants to engage in special pleading. But more to the point: extraordinary claims require extraordinary evidence, which “believers” can and will never provide.

Not quite. If someone says that “heaven” is a literal place that conforms to the same laws of physics with which we’re familiar, and it exists as a tetrahedron 100 miles on each face, floating 100 feet over the intersection of latitude 38 and longitude 122, we CAN indeed find proof of its existence or nonexistence.

By the same measure, we can determine that the “heavens” claimed by many religions are simply impossible to exist unless one wants to engage in special pleading. But more to the point: extraordinary claims require extraordinary evidence, which “believers” can and will never provide.

Perhaps someone ought to explain to this “engineer” what a shadow is (hint: they can’t exist in the dark). 

The notion of a shadow existing in the dark is as absurd as an echo existing in silence and a reflection in the absence of an object to be reflected.

“Does heaven exist?” is an example of a philosophical question because there is and can be no proof of its existence or non-existence. “Is this number on this machine caused by a ghost?” – for that question the overwhelming weight of evidence is that it is not.

Furthermore your last analogy isn’t very good because the device the cops use is actually BOTH a “doing more than the speed limit detector” and “an instrument to measure your speed”. They set the speed limit of the road they’re monitoring and an alarm goes off when a car exceeds that speed.

If he’s bereaved then his time and money and that of his customers would be better spent in counseling so they could maybe eventually get to a point where they enjoy life outside of a belief in the non-existent.

This guy is selling hope to people where absolutely no hope exists. Just because he can help people delude themselves for temporary emotional support doesn’t mean it’s a good thing for that person or the right thing to do. The undisputed scientific consensus is that this is bunk as bunk can be which means that the person he’s selling these flashing boxes to is going to either:
a) Believe this crap for the rest of their lives and waste their money and time chasing nothing.
b) Eventually realise they’re chasing nothing and then regret the years or decades they wasted and feel stupid for believing in such crap and trusting people who were well-meaning but batshit crazy.

When someone is making money off gullible people who should, but don’t know better then we are gonna think that person’s a jerk – even if he’s genuine in his trust of whatever snake oil or snake oil detector is being marketed. Acupuncturists are mostly well-meaning and likely believe the lies they tell people, but that doesn’t stop it from being immoral to waste their time, money and the homeostasis of their body by stabbing them with needles without gloves.

Didn’t need to read any more, superstitious nature explained.

Poor dude was abused as a kid.

I personally find the idea of life after death to be a great disapointment:  I was promised eternal rest.

Ta daaaaaaa!

The circuit described below was the basis of a fun science fair project (albeit with some added LEGO/aluminum foil/analog storage oscilloscope to make a triboelectric curve tracer).

 An electric field detector can be made for under $25, (or even less if one gets samples from TI):
 *use an op-amp such as the  LMC6001 (25fA leakage current, DIP), or even better the LMP7721  (3 fA leakage current, but unfortunately surface mount),
*wired as an impedance converter (output connected to inverting input, non-inverting input pin bent away from the chip as an antenna, [optionally with a spherical electrode on an insulating handle as with lab electrometers])
*with a split-power supply (even number of batteries with the ground at the mid-point between + and -) and
*filter the output with a 50 Hz twin-T filter (60 Hz in the US) – see “The Art of Electronics” by Horowitz and Hill p.279-80 for the filter design… 
*Never touch the op-amp chip with your bare hands. Any surface contamination will conduct, degrading the input impedance.

This is quite a fun toy, too.

I have no idea how this guy sells his kit, but logically, it’s not ‘detecting’ ghosts, but measuring phenomena which he claims is caused by them*.  So the ‘detector’ is not a scam, regardless of whether ghosts exist or not.

( * Assuming that it measures anything at all, of course.  If it doesn’t, then it *would* be a scam.  And it still wouldn’t have any bearing on the matter whether ghosts existed or not.)

EDIT: That wasn’t terribly clear, was it? I mean that whether ghosts exist — whether what you are measuring is *caused* by ghosts — is a philosophical problem. What you are measuring, and how accurately, is a science problem. Cops do not have a “doing more than the speed limit detector”. They have an instrument to measure your speed.

Hell, half of these things are probably bought by people who are just fans of Supernatural.

On a rational, logical level none.  In reality religion gets a pass because they are protected by the law somehow.

It’s also a way to give the ghosts total control over everything we think is random.

My kids love to go around the house with this: http://www.craftsman.com/shc/s/p_10155_12602_03482174000P?keyword=voltage+detector&prdNo=1&blockNo=1&blockType=L1 and detect “ghosts” around the house  haha!