The following post was originally posted on our Skeptiko forum but I liked it so much that I though of reposting it here. It was written by David Bailey, a regular on the forum and a proponent to the existence of psi phenomena.
Following much discussion on the forum and frustrated by how some skeptics lead the dialog, he posted the following hilarious post, written as an imaginary letter to a trainee skeptic.

Letter to a trainee skeptic – The Screwtype e-mails

You are now well advanced on your training to become a professional skeptic. If you perform well, this job can bring you many perks, such as appearances on television, and the opportunity to write a bestseller book. However, it is extremely important to learn throughly some simple rules that can help you in your craft. Remember, that while success will be rewarded well, failure will not be tolerated.

All being well, your first few efforts at debunking will be easy. There are, after all, a lot of crazy people in this world, and a fair few of them believe they have psychic powers. However, do not let these easy victories lull you into a false sense of security – sooner or later, you will come into contact with an altogether more tenacious kind of scientific heretic – one who has learned the ways of science and uses them against us! A careless encounter with one of these individuals can be utterly catastrophic:

Dialogues and Controversies – Controversies – The Telepathy Debate

or

http://www.sheldrake.org/realaudio/atkins_sheldrake.ram

If you fail an encounter with one of these people, you will be cast out of respectable scientific circles, and you career as professional skeptic will be over, so take extreme care to prepare for all such encounters.

These loathsome individuals perform actual experiments with controls and blind procedures, and statistical analysis – a shocking mockery of real science.

Let us take as an example the issue of dogs that know telepathically when their owners are coming home. Of course, you as a professional skeptic will state categorically that telepathy is against the laws of science, and so impossible in principle. This may well be sufficient for an unsophisticated audience, and you should never offer a more detailed explanation unless forced to do so. Your first line of defence should always be to point out that your busy schedule does not leave you time to debate with such deluded individuals – or even to read their ‘scientific papers’ in detail. If you use this tactic, it is, however, essential that you do read their ‘papers’ extremely thoroughly, or you will be caught out.

If you absolutely need to examine such a claim in detail, it is almost useless to analyse one of the ‘scientific papers’ that these vile creatures produce for statistical flaws – they are much too cunning to make mistakes like that. However, here are a few more subtle techniques to instill a decent respectable doubt in your audience. Remember – you only need to introduce doubt in your audience, nobody is going to actually test anything you say provided you sound vaguely plausible.

Let us say you have examined your opponent’s ‘data’ purporting to show the said telepathic link, and you can’t fault it on obvious grounds – enough tests have been done to prove statistical significance, any subjective assessments have been performed blind, etc. This is where you, as a professional skeptic, are supposed to show your worth in the job! Suggest something outrageous, such as the idea that the owner unconsciously leaves more dog food in the dish if he/she is going to be away for a longer period of time. Since your opponent will not have any information regarding the weight of food in the dish at the time of the experiment, this technique can be used to discard a large swathe of otherwise troublesome ‘data’. Remember, each time you can find a reason to discard a portion of your opponent’s precious ‘data’ you are lowering the statistical significance of what remains.

At this point, it may be tempting to accuse your opponent of incompetent science because he did not weigh the dog food in the dish, but if used at all, this ploy should be used very subtly. A side remark about how “genuine scientists always try to record all the relevant experimental data” is as far as you can safely go unless you have an unusually cooperative helpful audience. Even a highly skeptical audience usually likes to feel that you have dispatched your opponent in a fair and honorable manner!

Over time, many of our brethren have made great creative use of the idea that our opponents get their ‘results’ by cheating. You may very well feel that loathsome scientific heretics of this sort, are almost certain to cheat. However, once again, if you feel the need to use this ploy, your best approach should be indirect. You might, for example, comment that you were shocked to discover only after reading the ‘paper’ that the owner had entered his pet at Crufts. Anyone reading a sentence like that will be left with a vague sense of unease that the owner had an ulterior motive. Note that it does not really matter if a statement like this is true or not – if your opponent contests it, you can subsequently make very useful casual references to the ongoing uncertainty relating to this experiment.

Finally, remember that to become a truly great skeptic, you not only need to dispatch your opponent, but you should do it in style. Think of those melancholic pieces of classical music that come to an end in a paradoxical burst of optimism. When you are sure that your opponent is totally spent, jump up and shake his hand and offer him best wishes for his future research. It may be helpful at this point to explain that the only thing that keeps you in your career is the hope that one day you will finally encounter genuine evidence for paranormal phenomena, and that if your opponent can come up with such evidence you will, of course, be keen to examine it!

I hope these notes will help you prepare for battles to come.

Above all, put your trust in science, and I wish you a long and fruitful career!