Critical thinking

Hypnosis
Ghosts/hauntings
Telepathy
Mediumship/spiritualism
UFOs/Alien abductions
Crop circles
Dowsing
Stigmata
Telekinesis
Cold reading
Homeopathy

Critical thinking
This is a huge area, whole books have been written about how to think critically but this is an instant guide so well restrict ourselves to a few of the basics tools.

Occams Razor
A much loved principle among skeptics. Named after William of Ockham (I prefer Bill Ockham) who said something on the lines of, entities should not be multiplied beyond necessity only Bill said it in Latin. So what does this actually mean Its sometimes put as, the simplest explanation is most likely to be true. Notice most likely, this particular tool is no guarantee of proof. Simple example: I keep losing my car keys because invisible gnomes keep hiding them, or do I just forget where I left them Heres another example. Either mediums actually talk to the dead or they use cold reading (yes other possibilities may exist but Im only trying to illustrate the basic point). Starting with cold reading we know that this method (a catch all term for a variety of verbally dexterous techniques) can work. I know because Ive done it myself. We also know that the history of mediumship has been littered with fraud. On the other hand for the actual talking to the dead hypothesis to be true we have to make a number of unproven assumptions. E.g. our personalities can somehow survive death and communicate with certain gifted individuals. These souls appear to be able to see without eyes and speak without voice boxes as well as survive without nourishment. All our current science seems to show that without a functioning brain we do not maintain consciousness. Take your pick. I can hear you already saying Yes but what about my friend who was told... (add your own impossible fact). Which leads me to another tool in the box.

Anecdotal evidence
Someone tells you that theyve been abducted by aliens. They seem utterly sincere but you remain just a sliver of scepticism. Then you go to a UFO convention and you meet ten other people who also claim the same thing. Their stories have a certain similarity about them and now you think perhaps there is something in it. But what exactly Basically whereas you had one piece of weak evidence you now have ten more pieces of weak evidence. Eleven pieces of the same weak evidence do not strengthen the claim. I know it seems like it but it doesnt. You still only have the word of a few seemingly rational people. The problem is that the claim is rather extraordinary and the battle cry of the sceptic is, extraordinary claims require extraordinary evidence. A piece of alien technology that is completely unknown here on Earth would be extraordinary evidence. Alas anecdote is not sufficiently persuasive and its not science.

Appeals to ignorance
I saw him bend a spoon.
Perhaps it was sleight of hand
I know what I saw.
But magicians can bend spoons. Quickness of the hand and all that.
No I could see he didnt use any trickery.
Wow, theres no other explanation, it must have been supernatural.

What is being said here is basically, I dont know how it was done therefore it is paranormal. In actual fact all that can be said is, I dont know how it was done. There is no logic in saying, I cant explain it therefore it cannot be explained. Maybe no one can at the moment but just because we dont have an explanation to hand doesnt mean that none exist.

Its no good just claiming that because science cant explain it then it must be supernatural. Its not very satisfactory to support your argument by appeals to ignorance. How can aliens be here when the distance they would have to travel is so mind bogglingly huge Its a good question and just coming up with, well theyve probably developed technology we cant possibly understand is a bit of a weak response. It may even be true but if were limited only by our imagination then just about anything is possible.

Hypnosis
Okay youve see perfectly reasonable people on television or at a show doing completely stupid things because theyve been hypnotised. Youve heard about others who have had surgical operations without experiencing any pain. Still more have recalled forgotten memories of abuse suffered as children and even people who have remembered past lives. With all this going on youre thinking there has to be something in it. But is there

Martin Taylor is a hypnotist who does an act where no-one ever gets hypnotised. They do all the stupid, and it has to be said, amusing stuff that you see with real hypnotists but no hypnosis. Pain is a very subjective thing and people can tolerate different levels of pain. Why dont we all do away in anaesthetic Answer, because hypnosis only apparently works for a few people. Can anyone recall things more accurately because they are hypnotised Not that I know of.

There are two main theories about hypnosis the altered state theory and the social compliance theory. No one can demonstrate that there is any such thing as an 'altered state' but we know people will do things due to peer pressure etc. When a stage hypnotist gets volunteers from the audience he (or she) gets them to do a series of increasingly odd things until she (or he) is left with a core of willing volunteers.

You want to stop smoking or cure your fear of Michael Howard then dont rely on hypnosis to help you out. However the more you believe it will work the more likely youll get a result.

Dr Graham Wagstaff: http://www.i-psy.com/people/people_wagstaff.php

The Skeptics Dictionary: http://skepdic.com/hypnosis.html

Ghosts/hauntings
So youve seen a ghost or someone you know has seen one. Fair enough, what was it you actually saw Im not asking for a description such as a man in an Elizabethan costume carrying his head under his arm but I want to know what do you mean when you say youve seen a ghost There are a few possibilities. The spirit of a dead person or perhaps some sort of recording of a past event which is replayed under certain conditions. The again perhaps it was just something you misinterpreted. Pretty much everyone finds the last possibility very disappointing so lets start with the other two. A dead spirit eh Was this spirit dressed Do clothes have an afterlife How about ghost ships Do you think of a ghost as being non-physical If so how did you see it Light waves must have been reflected from its surface so that your eye could register it and send signals down your optic nerves to your brain. Did the ghost communicate in any way If so how did you hear it without sound waves How can something be non-physical and yet said to exist

There is of course no known mechanism by which events can be recorded in old brickwork (for example). Yes I realise video and DVDs can do it but theres a whole bundle of technology going on there from camera to DVD player, its an analogy but not an explanation. Perhaps well discover it you say, after all science doesnt know everything. Well that discovery will be Nobel Prize material but as far as Im aware no one is even considering it as even a remote possibility so it may be quite a wait.

We do know that people see things that arent there. We also know that many sightings happen a night under conditions of poor visibility and when the atmosphere is such that we are filled with a certain amount of expectation. To say youve seen a ghost is really not providing much information. You may well have seen something but not necessarily dead people.
See: Ghost hunting for beginners

Telepathy
Personally Im grateful that I can keep my thoughts to myself. Imagine a world where the government could tap into your thoughts and not just your phone. So how could it work Two possibilities spring to mind. Either its something physical and there is some physical transmission from one brain to another or its non-physical. If the first is true why cant we detect any means of transmission As Vic Stenger points out, scientists can detect the tiniest of things such as neutrinos. Neutrinos can pass right through you, me and the entire planet but we can detect them. Amazing and yet we cant find any mechanism from one brain to another. Another curiosity is that this energy is not hampered by such things as the inverse square law, i.e. the further you are away from the source of energy the weaker it gets. Can the brain generate enough power to transmit long distances No.

On the other hand it could be more supernatural in origin and not be physical at all. At this point we wave science a fond farewell and move into philosophy. Rene Decartes of I think therefore I am fame, thought there were two types of substance; physical and non-physical. The problem with the latter is that its a pretty odd concept. How can something be non-physical and yet be said to exist Beats me, but theres another problem. How can something physical interact with something non-physical. Think about it! No answer seems to present itself and good old Rene, along with every philosopher since, couldnt come up with an answer either.

Nevertheless for the sake of argument let's assume that a mechanism for telepathy could exist but we just haven't worked it out yet. Current testing for telepathy isn't trying to find the mechanism, it's trying to see if there is an effect at all and as far as I can tell, other than anecdotal evidence, there is no more reason to believe in telepathy than mentally being able to change lead into gold. Experiments using the Ganzfield techinque are being carried out at Edinburgh University but no breakthrough seems imminent.

Telepathy can appear to be real through trickery or sometimes through coincidences. A popular demonstration of telepathy is when a performer reproduces a drawing done by someone else. This is a trick pure and simple. Youre thinking of someone and they phone you within the next two minutes. It can happen and we dont need to rewrite the science books when it does.

Mediumship/spiritualism
Talking to the dead. Mediums are all over the place these days. The likes of Derek Acorah, Colin Fry, Shirley Ghostman turn up on our TV screens and have become national heroes, at least to some (yes I realise Shirley is a spoof do you realise the others are as well) Spiritualism is great at reinventing itself. It began with rapping noises and moved on to table tipping and other curiosities. Soon there were full physical manifestations of dead spirits followed by the scientific sounding ectoplasm. Alas no more, at least not in public. All we get now are the likes of Derek Acorah asking, Whos John

Do survive bodily death I doubt it. We evolved from simpler life forms and to think that somewhere along the journey, from single cell organism to human being, a benevolent god (I use this ill-defined word with caution) gave us souls makes no sense at all. What does make sense is that we do not want to accept the fact that we will cease to exist when we finally die. Mediums live off this fear but in fairness that isnt the same as saying they are deliberately conning us. The method they use is (usually) cold reading. This isnt just a question of making obvious statements it is a sometimes complex mix of different tactics and strategies that enable a medium (or astrologer, graphologist, tarot reader, palm reader, etc) to appear to be privy to information from an unearthly source. Much has been written about this technique and yet it is surprisingly still misunderstood. It is so good that the medium themselves can genuinely believe they have the gift. The method falls down when you start asking the medium to answer specific questions. My favourite being, What was my maternal Grandfathers nickname However if the medium manages to obtain personal information about you, either deliberately or by chance then this doesnt necessarily apply. One thing that you might like to consider is that most mediums will not allow themselves to be tested: the exception being when the scientist in question is a believer.

UFOs/Alien Abduction
To reach this planet alien spacecraft have to travel massive distances that are truly mind numbing to think about. Their craft is often reported as not being constrained by the laws of physics as we understand them. So what do they do when they arrive Well they like using farmers crops to make interesting patterns. If this gets boring they occasionally abduct people and stick things up their noses. They often show considerable interest in our genitalia. Sometimes they just buzz around with no particular purpose in mind. They seem to take steps to avoid our radar but dont mind being spotted by a lonesome truck driver.

Despite the huge number of sightings reported there is not one tiny shred of evidence the might give us some cause to consider that there may be something to this after all. Do you know how good the police are at collecting forensic evidence DNA can be collected from your breath on a window (or so Ive been told by the police). But in all these years of sightings, abductions and supposed government cover ups we dont have so much as an alien crisp packet.

Tell you what, when you have some hard evidence give me a call. Meanwhile talk to the Gray cause the Earthling aint listening.

Crop Circles
Look this is really easy. All crop circles can be made by people. Yes they are very clever and pretty but they bugger up farmers crops so stop it or pay the farmer. There is no rhyme nor reason for aliens to waste their time doing this. If you think they are youre beyond help.

Dowsing
A surprising number of people think this works. Yes the twig, pendulum or whatever moves but it moves due to the ideomotor effect and not because it can detect water, oil, gold, missing persons or dead bodies. Sometimes people will get lucky, in fact because of the water table here in the UK theres a damn good chance youll find water almost anywhere if you dig deep enough. What would prove this once and for all is for dowsers to show repeated success at properly conducted tests. Unfortunately what they show is repeated failure followed by repeated excuses. My suggestion is to buy the video from the Australian Skeptics and witness test after test followed by amazingly consistent results i.e. abject failure.

Stigmata
Since Francis of Asisi this phenomenon has caused the bewilderment of many. There are three popular theories;

a) God/Jesus or whoever causes this to happen by supernatural means.

b) The subject causes the injuries (whether real or fake) themselves.

c) Caused by the subconscious mind affecting the victim's body. Referred to as 'psychogenic purpura'.

My own view (applying Billy Ockham's theory) is that b) is the most likely candidate. For all I know c) remains a possibility but as this is controversial I'm sticking with b).

We never get to see the actual marks appearing by themselves, i.e. a camera fixed on the subject's hand and the gradual appearance of blood.

Here's the sort of thing I mean. Still photos of the various stages;

If you click each image you can see them in close up.
The stigmatic in this case did not wish to be identified. Okay it's my hand if you must know but this is strictly between you and me!

http://www.skepticssa.org.au/html/stigmata.html

http://skepdic.com/stigmata.html

http://paranormal.about.com/od/stigmata/

Telekinesis
Sometimes called psychokinesis, both words referring to the ability to physically move objects with the power of the mind. Grainy monochrome footage of Russian psychics moving things around arent particularly convincing even if you cant see the thread. Neither is making a compass needle twitch. Heres a question. What, apart from a psychic with powers that defy scientific explanation, can make a compass needle move

Calls cost a minimum of 25p.

Bending spoons comes under this heading. Just how the mind might do this is unclear. Via a spaceship from the planet Hoova is one possibility, using sleight of hand is another. Watching a magician make a spoon bend before your eyes can be both mystifying and entertaining. When you see one do it you should be generous with your applause as you may be witnessing great skill. If you want to know how its done then thats easy - buy a DVD or book from your local magic supplier. Then again just save your money and let me assure you, as someone who has bought the books and DVDs, I have never seen a psychic bend anything that could not also be accomplished by trickery.

Cold Reading
This is a catch all term that purports to explain how such things as astrology, graphology, fortune telling, tarot reading and apparent communication with the dead. Having successfully posed as a tarot reader and an astrologer on television I can vouch that it does actually work. Typical techniques include talking about general aspects of peoples lives that sound specific to them but in fact apply to most of us at one time or another.

For example:

"I see a celebration coming up soon, or perhaps ones just gone."

Birthdays are a pretty common occurrence and theres a reasonable chance this will be happening. Theres also house warmings, weddings and wedding anniversaries, and christenings.

"Theres a legal matter that youre concerned with. Could be a relative is up for armed robbery or maybe youre moving house."

There might be frequent questioning although they might be in disguise.

Whos George Or, Im getting the name George

Ive written more fully about this technique in Psychic Sophistry and Before You See a Psychic.

A number of magicians who specialise in producing psychic effects have accused me of exposing tricks by discussing cold reading to the point where some have refused to sell me certain items of a magicky nature. They seem to think that this technique is their sole property and anyway so what if a few people get ripped off along the way Needless to say I dont agree with this view and neither do many magicians. This technique goes back way before any psychic entertainer got hold of the idea and there are more important issues at stake than what is probably a tiny part of their act. Of course if they set themselves up as psychics then as far as Im concerned they are just perpetrating a fraud. I confess I have used cold reading techniques myself on occasion (as part of a trick) and even though I have explained it many times no one seems to spot it.

See also: James Randi's, "The Art of Cold Reading" and The Skeptic Dictionary

Homeopathy
This pretty much stands as a crowning glory to irrational thought. Despite all evidence to the contrary homeopathy has established itself as one of the most popular alternative therapies.

So you think it might work Well we all know the story that some medications (e.g. aspirin) began life as herbal medicine. So youre not going to rush to dismiss herbs, etc. out of hand are you You may well view homeopathy as being something quite similar to herbal medicine.

You may also have heard that one characteristic of the treatment is to dilute the substance to very small quantities. Well isnt that a similar way to how vaccines work You take a very small amount of the substance which triggers an immune response in your body or something like that.

Well no thats not what homeopathy is at all.

There are two main principles in homeopathy both of which are decidedly flaky. The first is that Like Cures Like. So if you feel all cold and shivery with a runny nose and a headache the stuff you take would, if administered normally, bring about similar symptoms. Think about this for a moment. Even though a virus may have brought this illness on, taking something that makes you feel just as bad supposedly helps alleviate it. Really

One website I found (http://www.practicalhealing.co.uk/) lists some of the things that homeopathy can be used to treat, e.g.

Bearing in mind our like cures like hypothesis what could we use for poor sleep Presumably caffeine fits the bill. How about hair loss I mean who decides what works What trials were done to arrive at these treatments

Still were only just starting. Heres the really weird bit. Homeopaths believe that the more you dilute something the stronger it gets, or at least the better its curative effect. Thats daft enough but it gets worse. The base substance (usually water) is diluted so much that the original treatment is completely missing. Thats right, all thats left is water. You simply add a small drop to sugar tablets and swallow hook, line and sinker!

The theory is that water somehow has a memory.

In 2002 the BBC programme Horizon (link below) tested this theory and James Randi stepped forward offering the JREF $1 million prize. Homeopathy failed dismally, much as you would expect but the most powerful point made by the programme (IMHO) was just what this diluted dosage means.

Take your substance (lets say caffeine) and mix it with 99 parts water. Bash it around a bit (called percussion) and you have a solution rated as 1C - then mix it some more.

Mixing it repeatedly this way eventually gets you to 6C which means we have the equivalent of 1 drop of caffeine in 20 swimming pools full of water. Mix it some more and youll get to 12C which equates to 1 drop in a body of water the size of the Atlantic Ocean. Move up to 30C, which is a common dose, and you wont have any of the original substance left. However that wont matter because youve been bashing it about between each dilution thus helping the water remember what was probably not an effective cure in the first place.

Horizon Homeopathy test
Skeptic's Dictionary
Belgian Skeptics attempt suicide
UK Skeptics on homeopathy

More to subjects follow.....