Dishonest Dembski:the Universal Probability Bound

One of the dishonest things that Dembski frequently does that really bugs me is take bogus arguments, and dress them up using mathematical terminology and verbosity to make them look more credible.

An example of this is Dembski’s *universal probability bound*. Dembski’s definition of the UPB from the [ICSID online encyclopedia][upb-icsid] is:

>A degree of improbability below which a specified event of that probability

>cannot reasonably be attributed to chance regardless of whatever

>probabilitistic resources from the known universe are factored in. Universal

>probability bounds have been estimated anywhere between 10^{-50} (Emile Borel)

>and 10^{-150} (William Dembski).

He’s quantified it in several different ways. I’ve found three different versions of the calculation of the UPB: two of them from wikipedia; one is from a message thread at ICSID which the author claims is a quote from one of Dembski’s books.

Let’s look at Dembski’s own words first:

>Specifically, within the known physical universe there are estimated to be no

>more than 10^{80} elementary particles. Moreover, the properties of matter are

>such that transitions from one state to another cannot occur at a rate faster

>that 10^{45} times per second. Finally, the universe itself is about a billion

>times younger than 10^{25} seconds (assuming the universe is around 10 to 20

>billion years old). ….these cosmological constraints imply that the total

>number of specified events throughout cosmic history cannot exceed

>10^{80} * 10^{45} x 10^{25} = 10^{150}.

He goes on to assert that this is the “maximum number of trials” that could have occurred since the beginning of the universe, and that for anything less likely than that which is observed to occur, it is not reasonable to say it is caused by chance.

Wikipedia presents this definition, and a more recent one which lowers the UPB, but as they don’t provide all of the details of the equation, I’ll skip it for now. Wikipedia’s explanation of this original form of the UPB is:

>Dembski’s original value for the universal probability bound is 1 in 10150,

>derived as the inverse of the product of the following approximate

>quantities:[11]

>

> * 10^{80}, the number of elementary particles in the observable

> universe.

> * 10^{45}, the maximum rate per second at which transitions in

> physical states can occur (i.e., the inverse of the Planck time).

> * 10^{25}, a billion times longer than the typical estimated age of

> the universe in seconds.

>

>Thus, 10^{150} = 10^{80} × 10^{45} × 10^{25}.

>Hence, this value corresponds to an upper limit on the number of physical

>events that could possibly have occurred since the big bang.

Here’s the fundamental dishonesty: None of those numbers have *anything* to do with what he’s supposedly trying to prove. He’s trying to create a formal-sounding version of the big-number problem by throwing together a bunch of fancy-sounding numbers, multiplying them together, and claiming that they somehow suddenly have meaning.

But they don’t.

It’s actually remarkably easy to show what utter nonsense this is. I’ll do a fancy one first, and a trivial one second.

Let’s create an incredibly simplified model of a region of space. Let’s say we have a cube of space, 1 kilometer on a side. Further, let’s suppose that this space contains 1000 particles, and they are all electrons. And further, let’s suppose that each 1mm cube in this cubic kilometer can only have one electron in it.

This is a model which is so much simpler than reality that it’s downright silly. But everything about the real world would make it more complex, and it’s sufficient for our purposes.

Now: consider the probability of any *configuration* of the electrons in the region of space. A configuration is a selection of the set of 1mm cubes that contain electrons. The number of different configurations of this region of space is (10^{9}!)/((1000!)\*(10^{9}-1000)!). That works out to (10^{9}\*(10^{9}-1)\*(10^{9}-2)\*…\*(10^{9}-1000))/(1000!).

1000! is roughly 4×10^{2568} according to my scheme interpreter. We’ll be generous, and use 1×10^{2569}, to make things easier. To estimate the numerator, we can treat it as (10^{9})\*((10^{8})^{999}), which will be much smaller. That’s 10^{7801}. So the probability of any particular configuration within that cube is 1 in 10^{5232}.

So any state of particles within that cube is an event with probability considerably smaller than 1 in 10^{5232}. So what Dembski is saying is that *every* possible configuration of matter in space in the entire universe is impossible without intelligent intervention.

And the trivial one? Grab two decks of distinguishable cards. Shuffle them together, and lay them out for a game of spider solitaire. What’s the probability of that particular lay of cards? 104! , or, very roughly, something larger than 1×10^{166}. Is god personally arranging ,my cards every time I play spider?

Anyone who’s ever taken any class on probability *knows* this stuff. One college level intro, and you know that routine daily events can have incredibly small probabilities – far smaller than his alleged UPB. But Dembski calls himself a mathematician, and he writes about probability quite frequently. As much as I’ve come to believe that he’s an idiot, things like this just don’t fit: he *must* know that this is wrong, but he continues to publish it anyway.

[upb-icsid]: http://www.iscid.org/encyclopedia/Universal_Probability_Bound