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Pre Implantation Genetic Diagnosis: What It Is (And Isn’t) Actually Capable Of

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There is a lot of talk about “Designer Babies”. Everybody knows that it is already possible to screen embryos for certain genetic diseases, so how far could we possibly be away from the process of picking and choosing specific traits for our babies, having them designed according to our wishes, have the modified embryo implanted, and nine month later giving birth to exactly the baby we wanted? Actually, can we even be sure the rich and powerful aren’t already secretly doing just that in shady hidden labs, run by megalomanic mad scientists? Are there already designed people walking among us?

The short answer is no. The technique used for avoiding genetic diseases in couples that have a high risk of giving birth to genetically impaired offspring is called Pre Implantation Genetic Diagnosis, usually shortened to “PGD” or “PIGD”.
Quite unlike what most people imagine, this doesn’t actually involve sequencing the embryo’s DNA: There is no doctor looking at thousands of lines of genetic code and saying stuff like: “it’s gonna be a tall blonde boy with an IQ of 126. Do you want us to remove his predisposition to alcoholism?”
In reality, PGD is very limited. The embryos are scrutinized at a stage when they consist of 8 cells. In this stage, all of the cells are still pluripotent (they haven’t specialized to be anything specific yet) and the embryo is still capable of being frozen and later reanimated without taking any damage. From these 8 cells, two are removed for the purpose of screening. That doesn’t impair the embryo, as at that stage the remaining six cells keep dividing into perfect copies of each other and the growth simply continues.
The two removed cells each contain two sets of chromosomes. That is very little genetic material to work with.

Two copies of each of the 23 human chromosomes.

Human DNA


With so little material, you have to know very specifically where to look and what you’re looking for in order to be able to spot anything at all. Sequencing the complete genome is not possible under these conditions. So “Screening” is limited to just that: Tests that check for a very specific genetic abnormalities in very specific places on the genome. In a healthy organism, every chromosome ought to be found twice in each cell. Some diseases are caused by one of these copies missing (monosomy), or there being three rather than two copies present (trisomy). These are the kind of genetic defects that we can spot with PGD. And that’s great, because it allows us to avoid some pretty horrible diseases. But all the hype is exaggerated: All those who are panicking because they think that if we don’t outlaw PGD, people will be able to walk into a clinic with a list of attributes they’d like their child to have, and be furnished with an accordingly designed embryo ready for implantation, have no idea what they are talking about.

Anything beyond recognizing the most obvious of oddities is still very much science fiction.

I Trust My Life To Science

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A few days ago I ordered two ten-gram-packs of Nux Vomica homeopathic remedy. Today I went to the pharmacy to pick it up. I paid a total of 16,60€, 8,30€ per pack. Nux Vomica, the listed active ingredient, is a poisonous tree native to india. Its seeds contain Strychnine, the bark contains the very similar brucine, aswell as other poisonous compounds.

Nux Vomica is potentially lethal to humans. 32 mg of strychnine are needed to kill and adult, so eating only a few Nux Vomica seeds would already do the trick. This is what such a death would look like:

Ten to twenty minutes after exposure, the body’s muscles begin to spasm, starting with the head and neck […]. The spasms then spread to every muscle in the body, with nearly continuous convulsions, and get worse at the slightest stimulus. The convulsions progress, increasing in intensity and frequency until the backbone arches continually. Convulsions lead to lactic acidosis, hyperthermia and rhabdomyolysis. These are followed by postictal depression. Death comes from asphyxiation caused by paralysis of the neural pathways that control breathing, or by exhaustion from the convulsions. The subject dies within 2–3 hours after exposure.

(Source: Wikipedia)

In a very small dose, Nux Vomica works as a laxative. In a higher dosis that is still below the lethal threshold, it leads to violent convulsions and muscle spasms.
As I said, I just legally purchased 20 grams of that stuff, at the pharmacy, without a prescription of any kind.

Tomorrow, I am going to swallow all of it.

Let me repeat: This is over the counter medicine, bought in a respected pharmacy. And not only does it clearly state a potentially lethal poison as the active ingredient on its label, but the package insert specifically warns not to take more than the recommended dose of five of the tiny sugar pills, and to immediately see a doctor in case of an overdose.

Despite all that I’m not the least bit worried about the consequences. I am not going to die. I am not even going to experience the slightest discomfort, beyond the taste of a mouthful of sugar. And that is because in homeopathic remedies, the active ingredient is diluted so much that there is absolutely nothing left of it.
Of course, homeopaths know that. They offer all kinds of excuses for why it might still work, mainly the claim that water has some sort of ability to retain a “memory” of the ingredient, and thus the desired effects, even in the absence of said ingredient. Of course, they might be right. Everybody has an anecdote of someone who is into homeopathy and was healed many times by it. So many people swear on its miraculous power, could they possibly all be wrong? Well, of course they could. And even though there are people who think that this is rather far-fetched and unlikely, I am willing to wager my life on it.The American Institute For The Destruction Of Tooth Fairy Science

My confidence will become more understandable the more you read about the supposed “science” behind homeopathy. Not only has it never conclusively been shown to work, there is not even a known mechanism or even hypotheses explaining how it might work.

The label on my recently bought bottles of homeopathic Nux Vomica – “remedy” also contains information on the concentration of active ingredient. Being an over the counter medicine, it has to. The concentration is given here is “D30” – a cryptic phrase, after all those who sell it are playing on the fact that hardly anybody knows about the principle behind it. What it means is that it has been diluted in a concentration of one in 10 raised to the power of 30. That’s a one followed by thirty zeroes:
1 in 1 000 000 000 000 000 000 000 000 000 000 – that means it’s a concentration of one molecule of active ingredient in 30 tons of water.
Which basically means that if you spill one drop of strychnine into the water of the New York Harbour, and I drink a glass of water from the Rotterdam Harbour, I have about as much chance to catch a molecule of active ingredient as by swallowing the sugar pills I just bought.

Standing in the Pharmacy with a bottle of homeopathic remedy in my hand that I had just bought and paid for, and generally being the guy I am, of course I couldn’t just leave without a comment. So I commented:

Excuse me, I’m wondering. I mean, why exactly do you sell these at all? As a Pharmacist you know that the only difference between all those bottles (I gestured at the rack behind her) is on the label, right?

She looked at me blankly, for a brief moment completely confused. Which is understandable. I mean, this wasn’t exactly fair. I came there prepared, while she was completely unsuspecting, thinking she was only dealing with a satisfied customer picking up his order when I jumped her with that question. Nevertheless, I felt I needed to make that point. Considering the situation, she kept her wits rather well.

Girl: “What do you mean?”
Me: “I mean that there’s no trace of any active ingredient in any of them. If you’d remove the labels, no homeopath in the world could tell the difference.”
Girl (confused): “But you just bought it!”
Me: “Yes, I’m with a group of skeptics who will collectively take an overdose tomorrow, to educate the public about the fact that there is nothing in it.”
Girl: “Oh, so you mean with the dilution and all”
Me: “Exactly.”
Girl: “Well, there are studies that show that it works, so…” (She left the sentence hanging)
Me: “Yeah, there’s about a handful of them. All of which have been discredited. On the other hand there are hundreds of credible ones that show no effect at all.”
Girl: “Well, there’s still thousands of people who will swear on it!”
Me: “Yes, but all they have to offer is anecdotes. There’s also thousands of people who swear on fortune-telling. Actually, there’s probably even thousands of people claiming to be the reincarnation of Napoleon. That doesn’t mean much.”
Girl: “Yes, but as long as it works for them, there’s no harm in selling it, no?”
Me: “Selling them sugar. At a price of eight euro per ten gram. No, that’s right I suppose. No harm. I just wonder about the ethics of it.”
Girl: “Well. You could talk to one of the pharmacists if you like.”
Me: “No, that’s alright. I’m not here to change anybody’s mind. I’m just making a point: Not all of your customers are happy about your support of pseudo-scientific woo. Have a nice day.”

Written by Phil

February 4, 2011 at 18:10

How Homeopathy Works

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Irreducible Complexity Has Been… Reduced. To Nothing.

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One of my favourite YouTubers, QualiaSoup, has put out another great educational video, addressing the “Intelligent Design” (=Creationist) argument of so-called “irreducible complexity”, which claims that evolution cannot be true since they are things that are so complex that they could not have come about by a gradual process like evolution by natural selection. The video dismantles the argument beautifully in very simple terms; it’s easy to understand and, more importantly, it’ll empower you to counter the argument yourself next time you come across it in a discussion.

One more thing: If you like QualiaSoup’s vids, be sure to check out his brother, too. He goes by the username TheraminTrees and produces videos of a very similar style which are just as brilliant.

On ‘Darwinism’

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I am not a ‘Darwinist’, and you aren’t, either. Period. First of all, the fact of Evolution by Natural Selection ought not to get too tied up to the person of Charles Darwin. Calling yourself a Darwinist implies a reverence of the person, rather than acknowledgement of the hard evidence in support of his theory. As much as Darwin is rightfully admired for one of the most important discoveries in the history of science, his person as such is completely irrelevant for the validity of the theory.

More important though is the use of the suffix -ism: It is nothing but creationist propaganda. -isms are worldviews, matters of opinion. Evolution by Natural Selection is not. Creationists started to call scientists who dared to point out the silliness of their beliefs ‘Darwinists’, in order to imply that they were a bunch of people sharing a common belief (as opposed to a bunch of people acknowledging the facts), people who have an agenda, people who probably have a evil conspiracy running to rid the schools of god. Because they hate god, those Darwinist do. Or so organizations like the Discovery Institute keep telling me.
It goes without saying that the same holds true for ‘Evolutionism’. You wouldn’t call yourself a ‘Newtonist’ or a ‘Gravitist’ just because you acknowledge the general explanation for why things are falling down. Even if Intelligent Falling were a serious movement rather than a (brilliant) parody, calling yourself a ‘Newtonist’ to show your opposition to it is destructive to your cause. Falsely calling scientific facts -isms is useless at best, but passing fact for opinion and acknowledging a controversy where there really is none at worst. Please don’t do that.

The ID-crowd should be viewed as the bunch of loonies they are, and safely be ignored. If you must address the ‘controversy’ at all, please don’t use terms that they made up. Taking them seriously can only leave the impression that their views actually have substance, which is simply not the case.

Debunking Creationist Claims is a Waste of Time

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Debunking creationists is a waste of time unless you do it publicly, on a large forum. This has to do with the Creationist’s intentions and tactics. We need to realize that they are not really interested in changing your mind in particular – they go only for a large number of people. Any people. Any “soul” that is “saved” is a success to them, and numbers is what matters here. This means that most creationists will not engage you seriously, but rather spend their time “saving” five less skeptical people instead of the one die-hard skeptic who has had his heart already hardened by Satan. Understanding this mind-set is crucial, because it makes a huge difference to how one should approach engaging them.

There is a statistical certainty at the heart of all creationist propaganda: The larger the number of people exposed to their ideas, the more will be among the crowd who are susceptible to their lies, ignorance and misrepresentations. If you can stand up and debunk all their arguments, they won’t care. They’ll simply move on to the next person willing to listen.
It has been shown time and time again that creationists tend to simply ignore the debunking of their claims – it is not important to them. As long as they can use a claim to “save” souls, they will continue to use it to do so.

Since their main concern is “saving” people, the arguments and all the pretend-science is only a means to an end. Their actual respect for the argumentative weight of scientific arguments is incredibly low. Hence, they will simply ignore what you have to say. Their mind-set is such that you cannot by scientific arguments change their views, since to them science is only one of many tools to employ to “do the lords work”. They hold it in low regard. So if you try to engage their arguments at their scientific face-value, showing them to be complete rubbish, they will simply laugh at how seriously you take all this science-stuff and how little you know about what (to them) is the real, important truth.

So if you ever engage in a discussion with a creationist, the listeners are what really matters. Your scientific arguments will not convince the creationist, but you might engage the common sense of the audience, inform them enough to vaccinate them against creationist propaganda.

Touchable Holograms

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Japanese scientists achieved quite an impressive feature: They created the world’s first touchable hologram. The Machine uses cameras (cannibalized from Nintendo wii-remotes) to determine the position of the user’s hand, and then creates a sensation of touch with the use of directed ultrasound. Very cool.

I want one.

Written by Phil

July 20, 2010 at 03:34

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