Friday, February 28, 2014

Bitcoin

Bitcoin has recently come into the news again because of the apparent collapse of its most important trading site "Mt. Gox".

I assume most people will know what Bitcoin is but in case you don't, it is supposed to be a kind of open source currency. It is neither backed nor controlled by any government or central bank, and it is supposedly untraceable, and apparently these features have made it very attractive to libertarians who are to varying degrees opposed to government regulation and taxation. And, one hears, also to other people who have even less wholesome reasons not to want their transactions traced.

Another feature of Bitcoin is that the maximum number of coins that can ever be generated is strictly limited. At the beginning it was very easy to "mine" additional coins, over time it gets harder, and at some point no more can be added to the system. This means that if Bitcoin gets used more and more, or even only if the economy grows, the value of this cyber currency will rise. In other words, Bitcoin has an in-built deflation mechanism, making all other goods cost less and less coins as time passes; the opposite of inflation. Of course this feature makes Bitcoin attractive to people with a somewhat gold bug-like psychology who believe that inflation is always bad if not downright evil.

With the problems of Mt. Gox news outlets have been discussing whether this will lead to the collapse of Bitcoin as a whole or whether the currency still has a bright future before it and is merely experiencing a hiccup. I am not an economist but I can imagine that it will recover; there surely appear to be enough True Believers out there to keep it going.

So it is well possible that Bitcoin will go on to be a success, the question is merely how you define success. Because it may well be a success as schmuck bait or an object of speculation, but it will never be a useful currency. And one does not have to be an economist to work that out.

Wednesday, February 26, 2014

Botany picture #143: Chrysocephalum baxteri


Chrysocephalum baxteri (Asteraceae), Victoria, 2012. This is one of my favourite everlasting paper daisies because it grows compact, is perennial in mild temperate areas, and produces many flowerheads. If we had a garden I would try to grow it there.

Tuesday, February 25, 2014

Folk understanding of Free Will, part 2: Hopeless confusion?

Continuing from here.

So, about those two studies on folk perceptions of determinism and incompatibilism; these are two different issues that need to be tested separately. First, do non-philosophers, do Joe and Jane Average believe that the world including ourselves is deterministic or do they believe that we have some magical ability of making decisions independently of cause-and-effect? Second, do they believe that free will, choice, moral responsibility and suchlike are still useful concepts under the assumption of determinism? In the second case, a yes would make them compatibilists, a no would make them incompatibilists. Both studies accordingly made an effort to test these questions one after the other.

The first study, Nahmias et al, presented its participants with a hypothetical supercomputer that could perfectly predict the future. It then first asked them whether such a scenario was possible. Subsequently, the participants were told to assume that all actions had been predicted by the supercomputer, and asked wether a hypothetical person called Jeremy acted out of his own free will and is morally responsible when predictably robbing a bank, going jogging or rescuing a child from death.

Results: The majority of participants answered that the above scenario was impossible. The overwhelming majority of participants answered that Jeremy had both free will and moral responsibility despite the determinist scenario they were told to assume.

The second study, Sarkissian et al, first presented its participants with two hypothetical universes: a universe A which is carefully described as deterministic and a universe B in which human decisions are "not completely caused by the past", and then asked them to decide "which of these universes is most like ours". Subsequently, the researchers asked the participants whether it is "possible for a person to be fully morally responsible for their actions" in the deterministic universe A. Note that this is a much less specific question than that used by Nahmias et al, and Sarkissian et al chose it on purpose, arguing that very specific questions such as about a bank heist would "trigger affective responses" instead of getting at people's theories of moral responsibility.

Result: The overwhelming majority of participants answered that universe B, the one in which human decisions are magically exempt from cause-and-effect, is most similar to our actual universe. The overwhelming majority of participants answered that "full moral responsibility" is not compatible with determinism. Interestingly, a determinist answer to the first question was very highly correlated with a compatibilist answer to the second.

Monday, February 24, 2014

Folk understanding of Free Will, part 1: Does it matter?

Over at one of my favourite blogs websites, two studies of folk philosophy have recently been discussed: what do average people, as opposed to trained philosophers, think about determinism and free will?

To recap, this is part of the greater controversy around compatibilism. Both compatibilists and incompatibilists assume that the universe we find ourselves in is essentially deterministic - with perhaps a bit of quantum randomness thrown in, but surely without any supernatural soul making decisions independently from the laws of physics.

However, compatibilists such as myself argue that even given complete determinism, there is still a significant difference between doing something voluntarily and doing something under coercion, or between doing something deliberately and doing it accidentally, or between being mentally sane and in control and being insane or drunk; and further, that terms like "free will", "choice" and "agency" are useful descriptors of these differences. Incompatibilists, on the other hand, do not believe that these terms make any sense given determinism.

As I have pointed out before, the funny thing is that all sane incompatibilists actually make the same difference in practice: they also treat an accident differently than harm that was caused deliberately, and they would also treat a lunatic but punish a sane criminal. So in practice every sane person is a compatibilist, and the only difference is semantic. Which is odd, because once you accept a difference, would it not be useful to have terms to describe it?

The argument made by incompatibilists for the rejection of these terms is ultimately that they are confusing, that they are loaded with supernatural meanings. They claim that when the average person hears "free will", they understand "supernatural soul doing things independently of deterministic laws of nature". And this is why we have to get rid of this terminology. I have never been able to accept this claim.

Friday, February 21, 2014

Why we are not getting killed by SkyNet any time soon

Computers are dumb.


For the benefit of non-German readers, this is a screenshot of the German Yahoo News site. The second paragraph starts with the phrase "the process initiated by her predecessor...", with the German word "der" being the direct counterpart of English "the" (for male nouns, that is, but let's not make this complicated).

Behind the German "the", some script has automatically inserted a share price at the Chinese stock market and a link to more stock market information. Why? The prominent box on the left provides the answer. It is not related to the article, which is not about stock markets at all but about the ministry of defense, nor is it some paid advertisement. Instead, the box has been added by the very same script, and it shows the recent development of share prices for a company called DER.

DER; "der Prozess". Get it?

It would be funny if it weren't so sad. (And annoying; let's not forget how annoying it is to have some stupid script clutter every text that contains the male definite article with irrelevant graphs and links).

And this is one of many reasons* why I am not afraid of a so-called technological singularity turning into Terminator: Rise of the Machines. Computers are idiots. Yes, they can do amazing things, but they are "oh look, she is trying feed herself with a spoon now, and most of it ends up in her lap, isn't that cute" amazing things, not "she is the greatest physicist of her generation" amazing things.

Of course, the computer is not really at fault, it is only a tool. Really one has to wonder about whoever wrote this script and thought it would be a great idea.

*) The other reasons are mostly variants on the observation that the singularity itself is a ridiculous idea.

Thursday, February 20, 2014

Botany picture #142: Soliva sessilis


Soliva sessilis (Asteraceae), Victoria, 2012. Australia has got its own burr-daisies in the genus Calotis. Their fruit are covered in spines, often barbed, that will stick to your clothes and are particularly nasty when stuck between the inner side of your shoe and your skin. But that wasn't enough of course. There is also Soliva sessilis, an invasive weed introduced from South America. It likes to grow in lawns where it is likely to be overlooked because of its small size and entirely green colouration - until you step on it with your bare feet. In the picture above a fruit is sticking in my fingertip.

Tuesday, February 18, 2014

Lawrence Krauss' A Universe from Nothing

To satisfy my curiosity about astrophysics, I have recently bought and have now finished reading A Universe from Nothing: Why There is Something Rather than Nothing, by physicist Lawrence Krauss. The book appears to have two aims: To give a summary of the current understanding of how the universe came to be, how it evolved into what it is now, and how it will end, and to refute the argument that some external (divine) intervention is necessary to get something from nothing.

Monday, February 17, 2014

Botany picture #141: Scabiosa ochroleuca


Scabiosa ochroleuca (Dipsaceae), Botanic Garden of Halle, Germany, 2007. The Dipsaceae are perhaps the plant family that the botanical novice in Europe will have the hardest time differentiating from the Asteraceae (daisies). They are somewhat related but not closely so, and they share capitulate inflorescences and even the transformation of the calyx into bristles or scales, as can be seen on the fruiting capitulum in the right lower corner. However, a closer look at the flowers will show crucial differences, for example free anthers in Dispaceae versus fused anthers in Asteraceae.

Here in Australia it isn't really an issue. There are no native Dipsaceae and only a few introduced ones. If anything, the daisies are confused with some Apiaceae.

Thursday, February 13, 2014

Identification keys: taxonomist-friendly versus user-friendly

An important part of my work are identification keys. Although multi-entry online keys are increasingly becoming available, the standard form they take is still after the fashion of a chose your own adventure book. The end-user - generally somebody who has a living plant, a dried specimen or, if they are unlucky, merely a photograph in front of them, is presented with a series of questions (couplets) with two possible answers each (leads). Every answer leads to the next question or ultimately to a group of organisms.

A simple example to demonstrate the principle:
1a. Vehicle has two wheels ... 2
1b. Vehicle has more than two wheels ... 3
2a. Engine present ... motorcycle
2b. Engine absent ... bicycle
3a. Vehicle has four wheels ... 4
3b. Vehicle has more than four wheels ...truck
4a. Vehicle carries few passengers ... automobile
4b. Vehicle carries dozens of passengers ... bus
Of course such a key is only as good as the taxonomist who writes it. In the above case I have, for example, glossed over the existence of small trucks with only four wheels. In reality, a plant taxonomist may have written a key that is similarly missing one species you can find in nature simply because it was unknown to them at the time.

However, that is not what I want to make the point of this post because we can rarely be sure that we have discovered all species and are aware of all variability out there in nature. What I want to write about today is a very specific way in which some of my colleagues in taxonomy fail to make their keys user-friendly.

Wednesday, February 12, 2014

Botany picture #140: Pistacia lentiscus


Pistacia lentiscus (Anacardiaceae), France, 2008. This is not the pistacio plant but one of its congeners. When I photographed it on a holiday trip to southern France I was unaware that the species is apparently harvested for a strongly aromatic resin, especially in Greece and Turkey. Read details at Wikipedia if interested.

Monday, February 10, 2014

More 'Framework': Can we trust molecular phylogenetics?

Continuing with extended comments on the book I am reading, Richard Zander's Framework for a Post-Phylogenetic Systematics.

In my previous post, I examined the claim that parsimony analyses are mislead by 'budding' speciation. As indicated then, this does not appear to be plausible unless we deliberately withhold information from the analysis, in which case the analysis itself would not be at fault.

However, it is not only parsimony analyses of morphological data that Zander mistrusts and considers to be too 'mechanistic'. He also claims that molecular phylogenetics cannot be trusted to infer the correct relationships between species. Although he uses different terms, partly of his own invention, his main argument appears to be that the stochastic nature of lineage sorting will often mislead phylogenetic analyses.

Creationists

Yes, perhaps reactions like these are mean, and perhaps those who have been raised in a culture of proud ignorance should be pitied rather than ridiculed, but I cannot help finding the following two links funny, especially the second one:

22 answers for creationists from someone who understands evolution

Creationist questions translated

Friday, February 7, 2014

Botany picture #139: cape weed


Arctotheca calendula (Asteraceae), Australian Capital Territory, 2013. This plant is commonly known here in Australia as cape weed after its introduction from South Africa. As one can see, it is actually quite pretty but it really is an obnoxious weed in disturbed areas and can cover large areas in good years. In contrast to many other daisies it does not have a bristly pappus. Instead, the fruits have a crown of scales and are covered with a large mass of fuzz.

Wednesday, February 5, 2014

Can parsimony analyses be mislead by 'budding' speciation?

In several places the Framework for a Post-Phylogenetic Systematics argues in favour of inferring relationships between groups of organisms with the informed intuition of the 'classical taxonomist' instead of 'mechanistic' phylogenetic analyses. It presents several arguments, among them the observation that classical taxonomy is generally based on more specimens per species than phylogenetics and the claim that neither parsimony analyses of morphological data nor molecular phylogenies can be trusted to infer relationships correctly.

I kind of get the first of these arguments, at least in principle. Yes, we could mention the large number of newly described species in classical taxonomy that are, at first at least, based on just the type collection. Yes, there seems to be some kind of conflation going on here between species delimitation, which to be done well indeed needs large numbers of specimens, and phylogenetics, which should preferably use only characters that are not variable within the species anyway and thus should theoretically work fine with only one specimen. But still one can at least grant that deep sampling is an advantage of the classical taxonomist's approach. (I would never argue against it anyway - alpha taxonomy and phylogenetics are complementary, not alternatives.)

But I do not at all understand the distrust of phylogenetic analyses. Consequently I would like to take a closer look at these methods, starting with the supposed vulnerability of parsimony analyses of morphological data. Specifically, the claim is that they can be mislead into inferring the wrong relationships if speciation is by budding, in other words if one of the two daughter lineages in a speciation event is morphologically indistinguishable from the ancestor (Framework p. 25, p. 39).

Tuesday, February 4, 2014

Botany picture #138: Malva neglecta


Malva neglecta (Malvaceae), Australian Capital Territory, 2013. This is an introduced weed, and the flower is tiny for a Malva, but I happen to like the genus.

Monday, February 3, 2014

Two possible meanings of "pseudoextinction"

Continuing to read Richard Zander's recently published Framework for Post-Phylogenetic Systematics.

I had originally intended to discuss general concepts instead of criticizing the book directly, but it probably cannot be avoided entirely; in the present case because I need to lead up to what I would like to discuss afterwards.

Repeatedly the book makes the argument that Hennig's internodal species concept is obviously wrong. To recapitulate, it is the idea that a species can be considered as existing through time between two lineage splits. On the tree of life, a species originates in a speciation event and ends at the next speciation event. Even if one of the products of that next split is morphologically and ecologically indistinguishable from it, it is still considered a new species. Because the ancestral species ends by definition at the split but is not really extinct (it survived, after all, in the form of both descendent species), it is sometimes called pseudoextinct.