What Fodor and Piattelli-Palmarini Got Wrong

Saturday, February 27, 2010 at 12:39 PM Bookmark and Share
There's been a bit of a stir the past few weeks over a book that recently came out titled What Darwin Got Wrong (which I haven't read... and probably won't).  In short, the book is written by a philosopher and cognitive scientist with apparently no expertise in evolutionary biology.  From what others have written, the book appears to assert that the theory of evolution is deeply flawed because the concept of natural selection is philosophically bogus.  Not surprisingly, a lot of biologists (and philosophers) take issue with that conclusion, and some are calling them out on their errors.

If you haven't heard of the book and how much the intelligent design (creationism) crowd is loving it, I'd encourage you to read up on the fracas here and here.  After that, there's a nice critique I'd urge you to read through titled "Misunderstanding Darwin: Natural selection’s secular critics get it wrong" by Ned Block and Philip Kitcher.

 - - - - Updated (2 March)

I neglected to mention that you can read more from Fodor and Piattelli-Palmarini here at The New Scientist. I'm not sure they really understand the theory of evolution by natural selection, especially when I read things like...

... it is not self-evident why species that have a recent common ancestor - as opposed, say, to species that share an ecology - are generally phenotypically similar. Darwin's theory of natural selection is intended to answer this question. Darwinists often say that natural selection provides the mechanism of evolution by offering an account of the transmission of phenotypic traits from generation to generation which, if correct, explains the connection between phenotypic similarity and common ancestry.

Moreover, it is perfectly general: it applies to any species, independent of what its phenotype may happen to be. And it is remarkably simple. In effect, the mechanism of trait transmission it postulates consists of a random generator of genotypic variants that produce the corresponding random phenotypic variations, and an environmental filter that selects among the latter according to their relative fitness. And that's all. Remarkable if true.

- - - -

After providing a biological perspective of the book's core argument, Block and Kitcher get into the philosophical argument -- and why it's irrelevant.  This requires some background (which they provide) on key concepts: intensional and extensional properties of a statement or claim.

You should really read their explanation, but as I (mis?)understand it, the gist of what F&PP got wrong was in asserting that natural-selection-in-action can't distinguish between a trait with fitness advantages and a tightly linked/correlated neutral trait that's just along for the ride. Who survives and reproduces is the same no matter which trait is advantageous.  Therefore, they seem to claim, natural selection is inadequate to provide an explanation for observed patterns of the diversity of life. Block and Kitcher rephrase F&PP's main contention as follows:
Here, then, is the problem restated: the causal processes at work in evolution cannot distinguish between coextensive properties, but selection-for requires that they be distinguished.
This (in my mind) points out their confusion about how natural selection works.  It isn't some sort of external force acting on populations of organisms, as they seem to present it. Instead it's merely a consequence of heritable traits resulting in differential reproduction and survival of individuals.  The causal mechanisms, as we understand them, work whether or not additional neutral traits are carried along for the ride.

After describing the problem with F&PP's argument against natural selection (which apparently has been criticized before) Block and Kitcher end their critique quite nicely...
Fodor and Piattelli-Palmarini take the role of philosophy to consist in part in minding other people’s business. We agree with the spirit behind this self-conception. Philosophy can sometimes help other areas of inquiry. Yet those who wish to help their neighbors are well advised to spend a little time discovering just what it is that those neighbors do, and those who wish to illuminate should be sensitive to charges that they are kicking up dust and spreading confusion. What Darwin Got Wrong shows no detailed engagement with the practice of evolutionary biology, nor does it respond to the many criticisms that have been leveled against earlier versions of its central ideas. In this latter respect, the authors resemble the creationist debaters who assert that evolution is incompatible with the second law of thermodynamics, hear detailed refutations of their charge, and repeat their patter in the next forum.

We admire the work that both Jerry Fodor and Massimo Piattelli-Palmarini have produced over many decades. We regret that two such distinguished authors have decided to publish a book so cavalier in its treatment of a serious science, so full of apparently scholarly discussions that rest on mistakes and confusions—and so predictably ripe for making mischief.
So what do you think?  Do Kitcher and Block have it right?

The Symphony of Science

 at 7:00 AM Bookmark and Share
Recently, I came across a website called "The Symphony of Science" by way of their youtube page. It's a pretty interesting endeavor by producer John Boswell towards an honorable goal: to "deliver scientific knowledge and philosophy in musical form."

Their latest video, The Poetry of Reality (An Anthem for Science), features a nice mix of popular skeptics and scientists - some of whom you are sure to recognize.  Check it out!

So far, they've produced a few videos and audio tracks which are available on their website (and youtube). It's not exactly the sort of music I'd expect to hit the top of the pop charts, but it's a pretty catchy way to present some (hopefully) thought provoking ideas to a wider audience.

Feel free to browse the videos and songs then share your thoughts in the comments below.

What Caused All These Dead Birds in Tennessee?

Friday, February 26, 2010 at 11:34 AM Bookmark and Share
Was it an outbreak of infectious disease? Did someone decide these birds were "agricultural pests" and deliberately poison them? Maybe they all were accidentally exposed to something toxic, or flew into traffic or power lines? Lots of folks down in Clarksville, Tennessee would love to know what actually killed a few hundred birds along a nearby road earlier this week...

Now, the birds shown are Red-winged Blackbirds and Common Grackles -- common species to find along side non-native European Starlings in big flocks of "blackbirds". From the condition and seemingly localized occurrence of the bird carcasses shown in the video, I'm pretty comfortable ruling out traffic or power-line collisions as the source of all these dead birds. I'd be much more included to put my money on poisoning... and probably deliberate poisoning.

Why? Well, this sort of thing actually isn't all that unheard of... Take, for example, a case from New Jersey which previously made the news when birds started actually falling from the sky.

[Source: WKRG.com News]

Oh, and if you wondered what was meant by "a permit" in the first video above, I should mention that the New Jersey incident (and this one from PA) were both part of control efforts. While hardly a pleasant sight, these large flocks of (mostly?) European Starlings were poisoned after consideration and approval by the USDA.

Getting back to the original question of "what happened?" we (fortunately) won't need to rely solely on speculation in this case! That said, we do still have to wait a bit and see what information comes back with those lab results...

(To be continued!)

Royal Society's Infectious Disease Articles: Free for February

Thursday, February 25, 2010 at 10:46 AM Bookmark and Share
The Royal Society is allowing free online access to some of their infectious disease articles through the end of the week. It's a bit of advertising on their part, but still an opportunity to skim the selection and maybe read an article or three.
All Royal Society infectious disease content is currently free to access.

The Royal Society's journals regularly publish content covering scientific research into infectious diseases and you can access all articles FREE until the end of February at:

Highlighted content includes:

'Livestock diseases and zoonoses', edited by FM Tomley and MW Shirley

'Airborne transmission of disease in hospitals', edited by I Eames, JW Tang,
Y Li and P Wilson

'The end of Kuru: 50 years of research into an extraordinary disease', edited
by J Collinge and MP Alpers

'Cross scale influences on epidemiological dynamics', edited by L Matthews
and D Haydon

Access all the above content - and more - FREE until the end of the week at:

We are particularly interested in receiving Theme proposals in this area of science. Find out more about how you can become one of our Guest Editors by contacting claire.rawlinson@royalsociety.org or visiting her at booth 14at the International Congress on Infectious Diseases in Miami on 9-12 March.

Mid-week Reptilian #11: Pituophis deppei jani

Wednesday, February 24, 2010 at 9:33 PM Bookmark and Share
I'm being totally unoriginal this week, but my cute little Northern Mexican Pinesnake (aka Jan's or Northern Mexican Bullsnake aka Pituophis deppei jani) was totally posing for me the other day, so I just had to snap photo of him/her. I couldn't resist sharing...

Figure 1: Pure, limb-free cuteness.

Snakes in the genus Pituophis are medium sized members of that very speciose family of snakes, Colubridae.  The genus is restricted to North America and northern Central America and their closest relatives are the new world "rat snakes" (don't use Elaphe... jump on the Pantherophis bandwagon!), plus other Lampropeltinines like the kingsnakes and milksnakes. Pituophis are primarily rodent specialists (many species are commonly known as "gopher snakes") and perhaps not surprisingly they can often be found in or around rodent burrows within their natural ranges.

One rather key bit of natural history of Northern Mexican Pinesnakes is that they come from the dry, open mountains of eastern Mexico. Living at these higher elevations, they have adapted to thrive at cooler temperatures than other Pituophis, have a slower metabolism, and can take 3-4 years to reach sexual maturity instead of the usual 1-2. There are two recognized subspecies P. deppei, the other being the nominate race, which occurs further south west than P.d. jani.

Figure 2: Distribution of P. deppei and the related P. lineaticolis,
modified by me from Rodriguez-Robles & De Jesus-Escobar 2000.
Orange curve roughly contains native range of P. d. jani... maybe.

As for the youngster in the picture above, it's only 7 months old, currently weighs in around 40 grams and is a little over 18 inches long.  Tiny considering that an adult can push 6-7 feet in length...

Figure 3: Hard at work, educating the public.

The first individual above was hatched by friend of mine this past fall - that's one of her adults at an educational event in the picture above. You can see even better photos of this big fella over at Biological Ramblings.

Homeopathy gets throat-punched then drop-kicked by British Parliment

Monday, February 22, 2010 at 11:20 AM Bookmark and Share
Over in the UK, a big report was released today by the Parlimentary Committee on Science and Technology. In it, homeopathy is basically called out as being ineffective pseudoscience, and bad medicine.  Reading a few of the points made in the report totally made my morning while I was waiting for some computer simulations (and some laundry) to finish!

There's a nice commentary and list of highlights over at Gimpy's Blog:
The Evidence Check on Homeopathy – a merciless punch to its vitalist organs (despite attempts to water down report).
You can also check out the short press release from the Science and Technology Committee
which also includes a link to the full report.

Atheist Bus Campaign Gets Animated

Saturday, February 20, 2010 at 8:32 PM Bookmark and Share

I have to say, it's unfortunate they included such an obvious error on this little animation. I mean, there certainly are "fortune tellers"... it's just that so far, they've failed to demonstrate any real supernatural abilities. ;)

Before you click that link above, I should warn you that the Wikipedia page on Fortune-telling is in dire need of a good "Criticisms" section.

[More details on the image at Science, Reason and Critical Thinking].

Global Warming means More Snow?

Tuesday, February 16, 2010 at 6:57 PM Bookmark and Share
True fact.  Check it out... this actually isn't all that hard of a concept to understand:
Memo to anti-science crowd:  Precipitation isn’t temperature!
Read more over at...
Massive moisture-driven extreme precipitation during warmest winter in the satellite record -- and the deniers say it disproves (!) climate science, by Jeff Masters | ClimateProgress.org 
If you're still not enticed to click, here's the data Jeff provides showing the global average temps for this winter (2009-2010). It's the little orange squiggle (rising above all the rest) on the left side of his temperature graph...

[ Data shown above are originally from http://discover.itsc.uah.edu/amsutemps/ ]

Mid-week Reptilian #10: Bipes biporus

 at 11:59 AM Bookmark and Share
Aside from actually posting weekly reptilian pics (sorry about that - grad school...) I thought I should try and put a little more diversity into the effort.  So this week, courtesy of James Gunn's "50 Freakiest Animals" I bring you the Ajolote (aka the Mexican Mole Lizard aka the Five-toed Worm Lizard aka the Baja Worm Lizard).

These reptiles are grouped with snakes and lizards in the order Squamata, but like other "worm lizards" they are distinct from both snakes (suborder Serpentes) and lizards (suborder Lacertilia), and have their own suborder Amphisbaenia

Bipes biporus is one of the four Amphsibaenians occurring in south western North America, which together comprise all four members of the genus Bipes and monophyletic family Bipedidae (the "two-legged worm lizards").  Like other worm lizards, it is a carnivorous burrowing species that tends to only venture into the open after dark.

R, I still love you, but I hate your round() function!

Monday, February 15, 2010 at 10:19 PM Bookmark and Share
You all remember the concept of rounding, right? I first learned to round numbers by taking them to the nearest integer (e.g. rounding 2.1 gives 2, rounding 3.9 gives 4, and so on) and in cases like 2.4 -- rounding up to the nearest integer.  I'll admit that as a child I didn't always pay attention in math class, but I was a bit surprised to learn recently that there are a number of different rules for rounding (and that being unaware of this fact can totally ruin your day).

How I came to choose this topic to blog about first requires sharing the following story... which I'll preface with a little background.

Dr. Wife and I both do work related to mathematical biology, and frequently use computers to tackle some of the more unruly bits of math we encounter.  Computer software for doing mathematics can roughly be divided into two main categories: The numerical software that crunches numbers  (not a technical term, I just like calling them number crunchers), and the computer algebra systems (or CASs).  This later variety do symbolic (or algebraic) manipulations like reducing fractions, and working with xs and ys instead of numbers.

For example, if you wanted to find a formula for the integral of 
x^2+sin(x) from x=a to x=b
software like Maple, Mathematica or the free software Maxima would tell you the answer is  

If it involves symbols, and algebraic manipulations - you want a CAS!

Now,if you just wanted to do something like plot data, generate random numbers or do statistical work -- computations using explicit numbers not just symbols -- then you'd want to use software that excels at crunching numbers.  Something like Matlab, Octave, R or programming languages like fortran, C, or python (just to name a few).

Quick tangent: while I'm a fan of Maple and Matlab, they cost money.  Enough  money that I'd rather use free alternatives when I can, especially if I might want to share my code with friends or collaborators but don't want them to spend money just to run it. Anyway, that's my plug for Maxima (a CAS) and R (statistical software that is also a great alternative to Matlab) -- but lets get back to the story...

The other day, Dr. Wife and I were working at home. She had a bug in some R code that -- after much hair-pulling -- was finally attributed to the following unexpected behavior of R's round() function:
> x = c(1, 1.5, 2, 2.5);
> rbind(x=x, round = round(x));
      [,1] [,2] [,3] [,4]
x        1  1.5    2  2.5
round    1  2.0    2  2.0
Notice there's something weird going on here... 1.5 gets rounded UP to 2 (as it should, if you think of rounding like most Americans), but 2.5 gets rounded DOWN to 2! What's going on with the round() function in R?!  Just to make sure I wasn't screwed over by all of my math teachers, I also checked in Matlab which gave the expected result...
> x=[1 1.5 2 2.5];
> [x; round(x)]
ans =
    1.0000    1.5000    2.0000    2.5000
    1.0000    2.0000    2.0000    3.0000
So what's going on here???

Quoting the wikipedia page on Rounding, there are different ways to round numbers depending on the task at hand...
  1. round to nearest: q is the integer that is closest to y...
  2. round towards zero (or truncate): q is the integer part of y, without its fraction digits.
  3. round down (or take the floor): q is the largest integer that does not exceed y.
  4. round up (or take the ceiling): q is the smallest integer that is not less than y.
  5. round away from 0: if y is an integer, q is y; else q is the integer that is closest to 0 and is such that y is between 0 and q.
Sadly, my favorite number crunching software (that would be R) uses one of the dumbest rules out there (well, dumb from a mathematical perspective) to decide what to do with numbers ending on ".5".  Both R and Matlab use the "round to the nearest neighbor" rule -- but the way they deal with the half-way point turns out to be the the source of the discrepancy above.

In school, most of us learned this rule (again, from the wikipedia page on Rounding):
Round half up

The following tie-breaking rule, called round half up, is widely used in many disciplines:
  • If the fraction of y is exactly .5, then q = y + 0.5
That is, half-way values y are always rounded up. For example, by this rule the value 23.5 gets rounded to 24, but -23.5 gets rounded to -23...
This is what Matlab does, and is what most people think of when they round numbers.

The numerical routines in R implement a different rule (italics added for emphasis):
Round half to even

A tie-breaking rule that is even less biased is round half to even, namely
  • If the fraction of y is 0.5, then q is the even integer nearest to y.
Thus, for example, +23.5 becomes +24, +22.5 becomes +22, -22.5 becomes -22, and -23.5 becomes -24. This variant of the round-to-nearest method is also called unbiased rounding, convergent rounding, statistician's rounding, Dutch rounding, Gaussian rounding, or bankers' rounding...
That's right -  R rounds to even.  Yes, it's primarily a stats platform. Yes, this is all explicitly stated in the documentation for the round() function, and of course I still love R, but seriously -- round to even?  To make matters worse, that day we also had other bugs that were essentially caused by the fact that (in both Matlab and R)
> (0.1+0.05) > 0.15
[1] TRUE 
So what's the moral of the story?  Well I'm not quite sure yet ... I still like R, and I certainly will continue to use it.  I'll probably end up reading through the documentation for frequently used functions -- not just unfamiliar functions -- and as much as I'd like to pretend it doesn't matter,I'll certainly keep an eye out for ways my code might get sabotaged by round-off error.

4000 year old human genome from Greenland

Sunday, February 14, 2010 at 11:29 PM Bookmark and Share
There's a nice post over at John Hawk's Weblog on the recent news that a group of researchers sequenced nearly 80% of the genome from a human that lived in Greenland nearly 4000 year ago.  The paper can be read in full online via Nature (PDF). If you're going to read the paper, do check out John's post for his commentary on the open and collaborative nature of this work.

2010 Great Backyard Bird Count!!

Saturday, February 13, 2010 at 1:17 AM Bookmark and Share
Looking for an excuse to get outside this weekend? Consider participating in the Great Backyard Bird Count! Go solo, take the family, maybe a friend or two, or maybe even join your local Audubon Society chapter or birding club and head outside to do some bird watching!

Aside from being a fun activity (and a great opportunity to learn more about your local birds), the data you collect are compiled along with data from thousands of others all across the country and made publicly available.  As of late Friday night, here's how many checklists have been submitted so far:

To give you an idea of what can be done with the data, here's an animated map of past observations of Common Redpolls in North America. This small northern finches tend to come down south for the winter -- but only every other year or so. This pattern can be seen in the data, as illustrated in this animated map...

More maps and data can be found on the Results section of the Great Backyard Bird Count website.

Creation "Museum" Part 5: Natural Selection vs. Evolution

Thursday, February 11, 2010 at 9:11 PM Bookmark and Share
~ Happy Darwin Day! ~

In honor of Chuck's 201st birthday (and the recent fuss over natural selection) I thought it appropriate to share some photos from a "Natural Selection is not Evolution" display from the Creation "Museum" in Kentucky.  During my visit in 2009, I managed to take photos of pretty much the whole display (which is a laughably transparent attempt to misrepresent the basic ideas of evolution and natural selection to promote AiG's particular brand of religious belief), which you can see below. This post is verbose, so feel free to just browse through the pictures (click on the images for a closer look).

The display is built on the usual creationist nonsense: e.g. that natural selection can't introduce new "information" (at least in the bizarre sense of the word used by many creationists), "mutations = loss of information", and lots of the usual equivocation with words like "kind." Like so many other displays in the "museum", it consists of a dash of selected scientific facts mixed with heaping piles of biblical literalisms and twisted logic.  Not surprisingly, this is a great recipe for generating some pretty dumb sounding statements like:
... speciation has never resulted in one kind of organism evolving into another kind, such as a reptile evolving into a bird.
and one of my favorite concluding remarks of all time:
Natural selection cannot (despite the common perception) be the mechanism for molecules-to-man evolution since it does not have the ability to create new genetic information (mutations cannot do this either).
The setup for their inevitable "we're right, science is wrong" punchline starts with the sign hanging from the ceiling in the display room.     

If you're wondering why they chose that title, the display goes on to imply the theory of biological evolution must be wrong because natural selection and evolution aren't the same thing... err, what?  Yes, evolution is not the same thing as natural selection, just like your car isn't the same thing as your steering wheel or that the rules of algebra aren't the same thing as all of mathematics.  None of this, of course, has any bearing on mathematics, your car, or the biological theory of evolution.

Now, in a real museum (remember, the Creation "Museum" is officially a ministry, not a science museum!) one would expect a display with a sign like this to clear up the basic definitions of and distinctions between these two concepts.  Presumably drafted with ulterior motives in mind (that or it was just really poorly done?), the first sign hints at a definition:

Sounds like a reasonable distinction between evolution and natural selection, right?  Well, not really... give it another read after you consider the following two points.

First, it's hard to deny - even for creationists - that natural selection happens. To accommodate this fact, a common approach seems to be to drive a wedge between microevolution and macroevolution.  Then, simply scoff at the notion of anything being "millions of years" old and blindly claim all the evidence supports microevolution but not macroevolution. Having done that, natural selection is no longer a problem.

Second, a big assertion in the "museum" is that creationist pseudoscientists and real scientists are all working with the same facts... that they just have different world views that influence their interpretation of those facts, and that these "competing world views" lead to the discord between the claims of real science and creationist pseudoscience.  This, of course, is complete BS.  You simply can't put science and religion on a level playing field.  By definition, creationists start with a core religious belief they assume to be true, then work to dismiss or rationalize away any evidence to the contrary. Real science works quite differently.

So what do they say about evolution and natural selection? First [bold emphasis is mine]...
Natural selection is the name Charles Darwin gave to an observable process, which results in small changes in the plant and animal world, such as fur color or plant height.
Here and in the next sentence, they still aren't giving any real definitions. Instead, they frame the conceptual relationship between evolution and natural selection as belief, then follow up with a bona fide (though quite unrelated) quote from legitimate scientists, just for a little credibility:
A common perception popularized by many scientists is that natural selection is a primary mechanism for evolution.  According to the National Academy of Sciences, "Natural selection... can have radically different evolutionary effects over different time scales."
If you feel like this sign is saying a lot between the lines, or if your BS detector is going off, you're on the right track!

Continuing with this sign, they again leave the reader free to associate scientific knowledge with personal belief. They give a nod to Darwin for getting the ball rolling, drop the phrase "millions of years" which I presume they repeatedly mention just to make other young-earth creationists snicker? They finish up the sign by priming the reader for more on this non-existent conflict between evolution and natural selection.
Darwin believed that given enough time (millions of years) natural selection could lead to large changes (such as a dinosaur evolving into a bird) and was the underlying mechanism of unobservable molecules-to-man evolution.  However, natural selection and evolution are different concepts, though today many mistakenly interchange the two.
After that primer, they take a stab at defining natural selection and evolution using factually reasonable but still disingenuous definitions of the two concepts:

Notice they leave the reader free to view these as lay terms, not specific scientific concepts:
Evolution - as commonly defined today - is the idea that all life on earth has come about through descent with modification from a single-celled common ancestor. We refer to this as molecule-to-man evolution. Inherent in this process is the requirement for origination of new genetic information as organisms evolve from simple to complex.
Here they mention a favorite flimsy and obvious straw man: the argument that mutation doesn't introduce "new genetic information" therefore the theory of evolution makes no sense (it turns out this requires you either ignore things like gene duplication and polyploidy, or make up your own very irrelevant definition of "information").

I laughed quietly to myself when I first read this next sign...

Despite the appearance that the sign may help clear up any lingering confusion about natural selection and evolution, it seems to instead dwell on the notion that natural selection is an insufficient mechanism for all of evolution. This, while true, is inconsequential and in this context quite misleading. 

On a side note, check out the rate of branching after the flood in that "Creation Orchard" figure (bottom right in the figure above), which some have called "super evolution" due to the wickedly high mutation rates needed for such rapid diversification:

The next few signs/dioramas illustrate a couple of cherry-picked examples presented as evidence that "mutation = loss of information" despite plenty of real evidence that various types of genetic mutation do indeed provide the extra genetic information needed evolution.  I'll leave it to you to ponder all the errors in the signs and read them without my interrupting.

(Closer look at the text in the above panel.)

Continuing on, there are more of these long-debunked creationist arguments against evolution. In particular, the infamously nebulous term "kind" which here seems to be something like the most recent common ancestors of (or all of?) a taxonomic family?  Again, having conceded that microevolution does happen, the belief that all of the "kinds" share no natural ancestry requires some effort to try and rationalize away all the evidence to the contrary.

If all this talk of evidence and arguments just doesn't appeal to you, fear not!  The ministry concludes wearing it's true colors: all you need to do is hang on to an unwavering belief in their particular version of Christianity, and the world will once again make complete sense.

PS:  If you're into knowing the source of your information (or just like sending thank you cards)...

Darwin Day in Columbus Ohio?

Tuesday, February 9, 2010 at 5:45 PM Bookmark and Share
I'm in Columbus, OH this week, where sadly there isn't much being advertised in celebration of Darwin Day this Friday.  That said, there are a few interesting events taking place later this week:


Skepticism and the Self-Correcting Nature of Science

Monday, February 8, 2010 at 12:42 PM Bookmark and Share
Over at The Times online, there's a nice article on skepticism and science by John Krebs. You might want to jump right over and check it out, or if you prefer a sample before committing to that mouse click, here's how the piece begins...
My non-scientist friends are beginning to ask me “What’s gone wrong with science?” Revelations about melting glaciers and potentially dodgy emails about global warming, the resurfacing of Andrew Wakefield and the MMR scare, and the sacking of the Government’s drugs adviser, have created the impression for some people that science is in a mess.

Of course science isn’t in a mess, nor has anything changed. But the stories underline two important features of scientists and science. First, scientists, just like every other trade — bus drivers, lawyers and bricklayers — are a mix. Most are pretty average, a few are geniuses, some are a bit thick, and some dishonest.

Second, science itself is often misunderstood. Scientists tend to be portrayed as voices of authority who are able to reveal truths about arcane problems, be it the nature of quarks or the molecular basis of ageing. In fact, science is almost the opposite of this. In The Trouble With Physics, physicist Lee Smolin considers how to describe science and concludes that Nobel Prize winner Richard Feyman’s phrase says it best: “Science is the organised scepticism in the reliability of expert opinion.”  ...

[Hat tip to Dave Hone]