# Everything existing in the universe is the fruit of chance and necessity

I've been informed that I've been at war for a while. I was surprised. Apparently, Perry Marshall thinks he's been firing salvo after salvo at me…I just hadn't noticed.

Oh, OK. I would just ignore him, but he's presenting some fascinatingly common misconceptions. One of his boogeymen is chance, and I've noticed that a lot of people hate the idea of chance. Uncle Fred got hit by lightning? He must have done something very bad. It can't just have been an accident. There are no accidents!

Yes, Virginia, there are accidents, chance events, and random happenings, and solid scientific explanations have to include chance variation as a component. Even consistently predictable events on a macro scale often have a strong stochastic element to their underlying mechanisms.

Marshall, unfortunately, has this wrong idea that invoking chance is a cop-out -- that randomness is bad and unscientific. So one of his salvos is a whole page of synonyms for random, which actually do more to reveal his ignorance than expose any problems with chance.

I don’t know
I don’t care
Can we go to lunch now
POOF!
Flying Spaghetti Monster
Magic
It wasn’t God so it must have been something else
Vague un-testable assertion that excuses me from doing my science job

Oh, rubbish.

Judging a pattern of variation to be random is determined by the actual properties of the data set. Randomness is an empirical conclusion.

Here's a simple example. I have a six-sided die. I throw it 666 times and record the result of each throw. What do you expect?

You probably expect about 111 "1"s, 111 "2"s, 111 "3"s, 111 "4"s, 111 "5"s, and 111 "6"s. But not exactly 111 of each; you expect some deviation from that number. You might actually suspect a non-random result if you got exactly 111 of each, because that would suggest some regularity. If the data showed that the first 111 throws all produced "1", the second 111 produced "2", etc., you'd immediately recognize that as non-random. That we can identify non-random series implies that we have some properties that we can examine to determine randomness.

We can even quantitatively predict properties of random sets of data; there are statistical theories and tests that can estimate how much variation we might expect from a given number of trials, how often and how long a run of repeated results should occur, etc. We can use these parameters to test for faked data, for instance.

To demonstrate this to beginning students of probability, I often ask them to do the following homework assignment the first day. They are either to flip a coin 200 times and record the results, or merely pretend to flip a coin and fake the results. The next day I amaze them by glancing at each student’s list and correctly separating nearly all the true from the faked data. The fact in this case is that in a truly random sequence of 200 tosses it is extremely likely that a run of six heads or six tails will occur (the exact probability is somewhat complicated to calculate), but the average person trying to fake such a sequence will rarely include runs of that length.

I've read whole books on the mathematical properties of randomness. I got into it for a while because of a problem that bugged me: I was watching the formation of peripheral sensory networks in zebrafish, which has both random and non-random aspects. Random: neurons grow out and branch in unpredictable ways; they don't form a methodical pattern, like a fishnet stocking covering the animal. The specifics of branching vary from animal to animal. Non-random: the dispersal of the branches has to demonstrate adequate spacing -- you shouldn't have clumping, or large gaps in the coverage. There were rules, but they played out on a game board where chance drove the particulars.

Or on a grander scale, read David Raup's Extinction: Bad Genes or Bad Luck?. The answer to the question is both, but luck is the best way to describe some large scale events in the history of life.

That's the important thing: many phenomena have an underlying basis in chance, and are subsequently shaped by non-chance processes: you can't model enzyme kinetics without acknowledging random molecular interactions given a direction by the laws of thermodynamics, for instance, or regard evolution without seeing the importance of chance variation, winnowed by selection.

And contra Marshall and a thousand other creationists, chance isn't simply the answer we give when we don't know what is going on. There are criteria. We have statistical tests for randomness and non-randomness, and we also use chance as a tool.

For example, one of the things I've been doing over this winter break is prepping some fly lines for mapping crosses my students will be doing in genetics next term. We use chance events to peek at the structure of the chromosome. Here's how it works.

We set up flies with pairs of traits (actually, we're doing three at a time, but that's more complicated to explain), and we generate heterozygotes that we are going to cross to homozygotes (or in this case, because these are X-linked traits, we can cross to hemizygous males…but see, it's already getting complicated). To keep it simple, here's an example of a fly that is heterozygous for two genes, one for body color and one for eye color. Wild type flies are gray-bodied, and we have a recessive mutant yellow that gives the body a yellowish cast. Wild type eyes are red, and we have another recessive mutant that has white eyes.

The female, on the left, has a gray body and red eyes, because those traits are dominant, but she's heterozygous, or a carrier for both recessive traits. The male has only one X chromosome, so he can only pass on the yellow and white traits, and he is also yellow bodied and white eyed.

As I've drawn them, if there is no other process in play, the female can pass on either a chromosome carrying yellow and white, or a chromosome carrying the gray and red traits (Note that I've faded out the male contribution: he's just donating solely recessive alleles to allow the female contribution to be expressed in the phenotype, so you can ignore him*). So by default, we'd expect that the result of this cross would be that half the progeny would be gray bodied and red eyed, and the other half would be yellow bodied and white eyed. Note that the half and half distribution is also a product of chance -- in most situations, which X chromosome gets passed on is random.

But there is another process in play! During meiosis, the female can swap around portions of her two X chromosomes in a process called recombination. This is a chance event. One chromosome is broken at a random point along its length, and the other chromosome is broken at the equivalent position (a non-random choice), and they're re-stitched together to form an intact chromosome with a different arrangement of the alleles. That allows some of the progeny to express a different pair of traits.

Every time you see a fly with red eyes and yellow body, or white eyes and gray body, in this cross, you are seeing the phenotypic expression of a recombination event between the two genes.

We can use this chance event to make a map of genes, an insight that came to Thomas Hunt Morgan and Alfred Sturtevant around 1911. Yes, genetics has been using chance to study genes for over a hundred years.

The way this works…imagine you have a barn. On the side of the barn, you paint two targets: one is a square 2 meters on a side, and the other is a smaller square, 1 meter on a side. You then blindfold a person with a gun, and tell them to blaze away in the general direction of the barn. At the end of the afternoon, after they've gone through a few boxes of ammo, you tell them the results: most of the time they completely missed the targets, but they hit the first one 18 times, and the second one 4 times.

Can they estimate the relative size of the two targets?

Of course they can. And the more shots they take, the more accurate their estimate will be.

That's what Sturtevant and Morgan were doing. They couldn't see genes, they could barely see the chromosome, but they could use recombination to take random shots at the arrangement of alleles on the chromosome, and they could see whether they hit that spot between two genes, like yellow and white, by looking for the rearrangement in the phenotype. The frequency of those rearrangements relative to misses also told them the relative size of the target -- how far apart yellow and white are on the chromosome.

(FYI, yellow and white are fairly close together, and we see recombination between them in only 1.5% of progeny of the cross. This gets reported as a map distance of 1.5 between yellow and white.)

You cannot predict ahead of time whether a specific individual produced in this cross will be wild type, or white-eyed and gray-bodied, or any particular possibility. It is a random process with a stochastic distribution of results that has some general predictability, just like an individual bullethole produced by the blindfolded shootist.

This seems to baffle creationists. They have a deep antipathy to randomness on principle, but even worse, they seem incapable of realizing that scientists can be simultaneously studying chance events that have statistically predictable outcomes -- like genetics, or evolution, or the physics of sub-atomic particles. It's a guaranteed way to blow their minds to point out that on one scale a phenomenon might be chance driven, but stepping back and looking at the whole reveals a regularity and pattern.

At which point they stagger back and declare that the small-scale events have to be determined and specified and predictable too, and therefore nothing is random. They just don't get it.

*Misandry!

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The Randomness of quantum mechanics implies chance. Still, it's sad Uncle Fred is dead. He was always good for a laugh and so handy with weather vanes and lighting rods.

“Everything existing in the universe is the fruit of chance and necessity.”

That is one purely subjective, philosophical, and non-scientific statement.

And as far as statements which are subjective, philosophical, and non-scientific, one of the more inane I’ve ever seen.

By See Noevo (not verified) on 11 Jan 2016 #permalink

This may go a little way toward getting at why so many people are averse to "chance":

(Speaking from the perspective of having long ago accustomed myself to the elements of determinism, randomicity, and chaos in events at-large and in my own cognition.)

Given that observable phenomena in the known universe operate along a continuum from strongly deterministic to random. Humans generally act based on a subjective sense of agency. The word "chance" is loaded with emotional meanings that are entirely different to those associated with "randomicity." Chance implies pure happenstance, and "happenstance is not a stance:" that is, it is felt to be devoid of agency in a manner that is subjectively different to randomness.

Agency is roughly synonymous with will, whereby we introduce another point on the spectrum between wholly-determined and wholly-random, which is to say, "free will." It is presently fashionable to hold that free will does not exist _at all_, which is to say, 0.000% of human cognition and behavior. Strictly speaking that proposition is as empirically unfalsifiable as theism and atheism: the failure of a hypothetical test based on predicting an individual's behavior could be attributed to underlying hard-deterministic causal paths that resulted in the test failing, so the negative finding is taken as "proof" (sic) of the positive. There's a word for that particular logic error but it escapes me at the moment (having just pulled an all-nighter at work).

Conversely, the proposition that will is entirely free is easily falsified by numerous readily-predictable aspects of cognition and behavior: for example emotional reactions to kind words or hostile words. One hardly needs to elaborate further than the colloquialism about having one's "buttons pushed."

If I had to put a number on it, I would say that will is 90% determined, such as through genetics, neurobiology, and emotional reactions to social stimuli, and perhaps 10% "free" in the sense of being at root a matter of free choice or an uncaused cause. (If we're to believe that the origins of the universe are an uncaused cause, then we can't reasonably hold that this was the one singular instance of such, any more than fundamentalisms of various denominations can reasonably assert that their particular revealed truths were the only such divine-origin truths in human history.)

Regardless of where one stands on the subject of freedom of will, the fact remains that humans act with a sense of agency, and will react against what they perceive as efforts to deny a core aspect of their sense of humanity.

I'm inclined to believe that we need to do quite a bit better in our attempts to communicate ideas such as determinism and randomicity. Any implied sense that one seeks to impose one's will, even if better-informed, upon another, will backfire and produce reactions against the entire worldview that is communicated in that manner. But an appeal to the greater whole, in which each of us are a part, is more likely to succeed.

Who among us would not wish to be part of the cosmic dance, the inspiring beauty of nature at all scales from subatomic to astrophysical? Who among us doesn't look in wonder at the precision of classical mechanics in the orbits of planets around the Sun, feel a sense of gratitude for medicines that bring an end to the suffering of disease, or contemplate the wave/particle duality as a deep mystery of existence? Those feelings are quite contagious, and they bring with them the desire to learn more. Therein resides a path toward wider interest, and perhaps wider agreement.

To G:

“If I had to put a number on it, I would say that will is 90% determined, such as through genetics, neurobiology, and emotional reactions to social stimuli, and perhaps 10% “free” in the sense of being at root a matter of free choice or an uncaused cause.”

Which 10% of your lengthy comment #5 would you say is due to your free choice?

By See Noevo (not verified) on 12 Jan 2016 #permalink

Hi See-

In fact that entire piece was written in one pass, in a particular altered state that occurs usually late at night but can also occur after a relentlessly long work shift with sleep deprivation such as I was just wrapping up when I wrote it. The output of that state resembles the output of the state induced by approx. 1/5 of a clinical dose of a psychedelic such as psilocybin, but the subjective sensation is somewhat different, more akin to a high-concentration "work trance" but with greater access to the kind of free association that is typically used in writing fiction. I recognize a number of elements of that state as having neurochemical causes, or at minimum, neurochemical correlates; and my writing style is influenced by a number of other authors; but the output is original in the same manner as other types of writing.

Where the 10% comes in, is in guiding the creative mood in a chosen direction and then in editing what's being written. By analogy a 180-lb. driver drives an 1,800-lb. car, and the car proceeds along as a deterministic classical mechanism occasionally influenced by random factors and chaotic factors such as unexpected potholes and traffic flows.

In the driver's seat one can hypothesize the soul per traditional religious interpretations, or one might hypothesize some further physical mechanisms e.g. per Penrose & Hameroff's theory of neural computation, or some combination of both per an interactionist theory of mind that might be one click to the "left" (or to the "right" if one prefers) of David Chalmers. But although the driver depends on the vehicle (and in another sense the vehicle depends on the driver), they are not identical, and upon reaching the destination they are separable, and therein the metaphor spawns the usual debates about the nature of mind.

@G-great explanation!

Hi Chris- Thanks!

One of the things I seek to do here and elsewhere, is to seek common ground of underlying values that are shared between people of substantially differing worldviews.

For example to my mind, the fact of randomicity in nature neither favors nor disfavors theistic beliefs. The way we communicate these ideas is critical to the way they are received.

Rather than try to convince others of the rightness of our beliefs about untestable propositions, it's better to seek the shared ground of mutual agreement on values. For example all reasonable people agree that the law should bear no bias toward or against any particular beliefs in the area of religion, and all reasonable people agree that individuals should be treated as having personal agency.

In that context, there is no harm in agreeing that empirical studies of genetics depend on certain assumptions about random factors in gene expression. Some of these findings, as with other findings including many we take for granted as entirely mundane, are good subjects for contemplation, within the scope of whatever worldview one has.

In the driver’s seat one can hypothesize the soul per traditional religious interpretations, or one might hypothesize some further physical mechanisms

or one could take the evidence based approach and realize there is nothing at all that supports the notion of a soul - but that is contrary to what morons like sn believe.

G, your 90/10 is sickeningly arbitrary. Ask yourself this: if the 90% can be assumed to be deterministic, why can't the 10% be assumed to be merely more difficult to decipher as deterministic? The whole problem surrounding this 'debate' is that 'free will' is about as coherent a concept as 'god' (that is, entirely incoherent).

By Matt Marcinkiewicz (not verified) on 21 Jan 2016 #permalink

I hope you're G-forced to reconsider your laughable line of argument, G.

By Matt Marcinkiewicz (not verified) on 21 Jan 2016 #permalink