Weiye Loh's Library tagged Causation → View Popular, Search in Google

Jan

2012

Rationally Speaking: Rationally Speaking encore: Wittgenstein vs Freud vs Schopenhauer

I don't see why causes have to be deterministic. We know (for example from quantum mechanics) that there is such a thing as probabilistic causality (though that still doesn't rescue free will, since we would at most have a random will). Second, Wittgenstein, like so many anti-physicalists, simply (conveniently) neglects to give an alternative explanation. If reasons are not a particular instance of causes, what are they, exactly? Inquiring minds want to know, and for good reasons.

rationallyspeaking.blogspot.com/...aking-encore-wittgenstein.html

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Free Will Determinism Causation Reason

Here is what Wittgenstein says: "The proposition that your action has such and such a cause is a hypothesis. The hypothesis is well-founded if one has had a number of experiences which ... agree in showing that your action is the regular sequel of certain conditions which we then call causes of the action. In order to know the reason which you had for making a certain statement ... no number of agreeing experiences is necessary, and the statement of your reason is not a hypothesis."

OK, Witty is always difficult to read, but it seems that what he is saying is that causes are hypotheses about how events are connected in the world. Reasons, on the other hand, are justifications that we give for certain actions or propositions. Perhaps an example will clarify: if I hit your knee with a small hammer, your leg will move because of a reflex. I.e., the hit, through a series of physical connections, caused the leg to move. However, if I ask you to raise your leg and you do it, your reason for doing so is that I asked you to perform the action. Wittgenstein is saying that reasons aren't causes, they are an altogether different kind of beast. This distinction does have great intuitive appeal, as we all realize that there seem indeed to be a big difference between the two cases concerning your knee just described.
Arthur (Schopenhauer), on the other hand, said about such matters: "Motivation [i.e., reason] is causality seen from within. ... Motivation [is only] causality passing through knowledge."
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- Wittgenstein seemed to prefer a distinction between causes and reasons for two, well, reasons! First, he was always distrustful of excessively scientifical or physical explanations of the human condition, especially of mental phenomena. Second, he felt that if one explains actions in terms of causes, then one is committed to an automatic form of determinism, and there goes free will out the window. Consciousness, then, is an after-the-fact illusion, a fiction that allows us to think that "we" make decisions, when in fact it's all a matter of physical causes.

Aug

2011

Trying to Live Forever - NYTimes.com

opinionator.blogs.nytimes.com/...trying-to-live-forever

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Correlation Causation Life Information Overload Health Medicine Science

An article in the May Consumer Reports Health shed some light on this question. It discussed the widely publicized medical study that showed, contrary to expectations, that “raising HDL (good) cholesterol with drugs did nothing to protect against heart attacks.” This, the article said, was surprising because observational studies had shown that people with lower levels of HDL had more heart attacks than those with higher levels of HDL. An observational study, however, shows only a correlation between two variables (e.g., level of HDL and number of heart attacks). The new result came from a randomized clinical study, using one group of patients who receive a given treatment and a “control group” of patients who do not. Unlike an observational study, such a study can show whether or not, for example, higher HDL actually prevents heart attacks. The article went on to emphasize that “we should almost never rely on the results of observational studies, which can only suggest associations with disease but not prove them.”
implicit in most media reports, is that acting on the results of the unreliable observational studies “couldn’t hurt and might help.” This makes sense if I have a medical problem for which there is no reliable remedy. If nothing else has helped my arthritis, insomnia or back pain, it would make perfect sense to try a remedy that will not do serious harm and has some probability of working.
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- But most observational studies concern not remedies for present ills but protection against future ones, and for these cases it is hard to tell if even relatively small costs or risks of harm outweigh the probability of partial protection
- More important, there is a reasonable chance that further observational studies will call into question the one I’m acting on or even
- it would seem preferable to keep healthy by a method that is simple, reliable and doesn’t require constant revision and fine-tuning. We do, after all, have such a method available: simply follow the humdrum standard advice we’ve heard all our lives about eating sensibly, exercising regularly, and having recommended medical tests and exams. Doing this and foregoing the endless calibration of our behavior to the latest research results will be far less stressful, make it more likely that we’ll stick to the method, and allow more time for fulfilling pursuits. From this point of view, the media’s constant updates on the latest observational studies are counterproductive.

Jun

2011

New research an eye opener on cause of myopia - CNN.com

While the belief that prolonged close-up activities like reading and playing computer games cause short sightedness (myopia) is popularly held, new research indicates that a deficiency of sunlight is the true culprit.

Many epidemiological studies have examined the issue of computer, video and television based activities on the eye health of children and have found no association between time spent using digital media and the development of myopia. While it is an intuitive association to make, it simply has not been confirmed. There are some studies that have found an association between the time spent doing near-work activities such as reading and studying, but the results are inconsistent and marginal. There may be an indirect link where children have substituted large amounts of time spent outside with these activities.

edition.cnn.com/...index.html

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Myopia Causation Correlation Science Health

his finding has now been confirmed in a number of other studies from the U.S., Singapore and China. Our hypothesis that the mechanism of the effect of light was mediated by retinal dopamine, a known inhibitor of eye growth whose release is stimulated by light, has also been supported by animal experiments. All of these studies confirm a consistent link between the time spent outdoors and the prevention of myopia, possibly crucially mediated by the at least ten-fold increase in light levels between indoor lighting and being outside. So yes, it is highly likely that there is a direct connection between time spent outside and preventing myopia.
the effect of light on the prevention of the development of myopia may have a threshold effect, that is both the level of light required and the duration of light exposure may need to reach critical amounts before light has its preventive effect.
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- There is no evidence either way that wearing glasses has no effect or hinders the protective effect of sunlight, but this has not been studied systematically.
  
  Young children tend not to routinely wear sunglasses, possibly due to high rates of breakage and general intolerance to wearing glasses. In Australia wearing hats is compulsory at primary school and is encouraged for outdoor activities, but again this seems not to have reduced the protective effect of being outdoors. This may be because even with a hat the level of illumination outside is still so high.
- The differences between countries seem to relate to high levels of myopia in highly urbanized, academically focused countries with an emphasis on early competitive education systems versus low levels in less urbanized and/or countries with more emphasis on learning through play at an early age.
  
  Scandinavian countries seem no more myopic or otherwise than other more southern European countries. In part this may be lifestyle as people with limited sunlight during winter seem to get outside for long hours during the summer which may balance the short available sunlight hours in the winter. However, there is some limited evidence that in these countries, the rate of eye growth advances more in winter and slows in the summer.

Jun

2011

Don’t Miss this Video: “A link between climate change and Joplin tornadoes? Never.” « Climate Denial Crock of the Week

The video takes Bill Mckibben’s recent editorial from the Washington Post, sets it to music and powerful video of the last year’s weather events.

If you haven’t seen the editorial, give that a look first. It starts out -

Caution: It is vitally important not to make connections. When you see pictures of rubble like this week’s shots from Joplin, Mo., you should not wonder: Is this somehow related to the tornado outbreak three weeks ago in Tuscaloosa, Ala., or the enormous outbreak a couple of weeks before that (which, together, comprised the most active April for tornadoes in U.S. history). No, that doesn’t mean a thing.

It is far better to think of these as isolated, unpredictable, discrete events. It is not advisable to try to connect them in your mind with, say, the fires burning across Texas — fires that have burned more of America at this point this year than any wildfires have in previous years. Texas, and adjoining parts of Oklahoma and New Mexico, are drier than they’ve ever been — the drought is worse than that of the Dust Bowl. But do not wonder if they’re somehow connected.

climatecrocks.com/...nge-and-joplin-tornadoes-never

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Climate Science Causation Correlation Uncertainty Rhetoric

May

2011

It’s Even Less in Your Genes by Richard C. Lewontin | The New York Review of Books

In trying to analyze the natural world, scientists are seldom aware of the degree to which their ideas are influenced both by their way of perceiving the everyday world and by the constraints that our cognitive development puts on our formulations. At every moment of perception of the world around us, we isolate objects as discrete entities with clear boundaries while we relegate the rest to a background in which the objects exist.

That tendency, as Evelyn Fox Keller’s new book suggests, is one of the most powerful influences on our scientific understanding. As we change our intent, also we identify anew what is object and what is background.

www.nybooks.com/...its-even-less-your-genes

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Genetic Nature Nurture Causation Heritable Heritability

Although classic Darwinism is framed by referring to organisms adapting to environments, the actual process of evolution involves the creation of new “ecological niches” as new life forms come into existence. Part of the ecological niche of an earthworm is the tunnel excavated by the worm and part of the ecological niche of a tree is the assemblage of fungi associated with the tree’s root system that provide it with nutrients.
The vulgarization of Darwinism that sees the “struggle for existence” as nothing but the competition for some environmental resource in short supply ignores the large body of evidence about the actual complexity of the relationship between organisms and their resources. First, despite the standard models created by ecologists in which survivorship decreases with increasing population density, the survival of individuals in a population is often greatest not when their “competitors” are at their lowest density but at an intermediate one. That is because organisms are involved not only in the consumption of resources, but in their creation as well. For example, in fruit flies, which live on yeast, the worm-like immature stages of the fly tunnel into rotting fruit, creating more surface on which the yeast can grow, so that, up to a point, the more larvae, the greater the amount of food available. Fruit flies are not only consumers but also farmers.
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- Second, the presence in close proximity of individual organisms that are genetically different can increase the growth rate of a given type, presumably since they exude growth-promoting substances into the soil. If a rice plant of a particular type is planted so that it is surrounded by rice plants of a different type, it will give a higher yield than if surrounded by its own type. This phenomenon, known for more than a half-century, is the basis of a common practice of mixed-variety rice cultivation in China, and mixed-crop planting has become a method used by practitioners of organic agriculture.
- Despite the evidence that organisms do not simply use resources present in the environment but, through their life activities, produce such resources and manufacture their environments, the distinction between organisms and their environments remains deeply embedded in our consciousness
- the problem is deeper than simply intellectual inertia. It goes back, ultimately, to the unconsidered differentiations we make—at every moment when we distinguish among objects—between those in the foreground of our consciousness and the background places in which the objects happen to be situated. Moreover, this distinction creates a hierarchy of objects. We are conscious not only of the skin that encloses and defines the object, but of bits and pieces of that object, each of which must have its own “skin.” That is the problem of anatomization. A car has a motor and brakes and a transmission and an outer body that, at appropriate moments, become separate objects of our consciousness, objects that at least some knowledgeable person recognizes as coherent entities.
- Evelyn Fox Keller sees “The Mirage of a Space Between Nature and Nurture” as a consequence of our false division of the world into living objects without sufficient consideration of the external milieu in which they are embedded, since organisms help create effective environments through their own life activities. Fox Keller is one of the most sophisticated and intelligent analysts of the social and psychological forces that operate in intellectual life and, in particular, of the relation of gender in our society both to the creation and acceptance of scientific ideas. The central point of her analysis has been that gender itself (as opposed to sex) is socially constructed, and that construction has influenced the development of science:
  If there is a single point on which all feminist scholarship…has converged, it is the importance of recognizing the social construction of gender…. All of my work on gender and science proceeds from this basic recognition. My endeavor has been to call attention to the ways in which the social construction of a binary opposition between “masculine” and “feminine” has influenced the social construction of science.
- It is, for example, all very well to say that genetic variation is responsible for 76 percent of the observed variation in adult height among American women while the remaining 24 percent is a consequence of differences in nutrition. The implication is that if all variation in nutrition were abolished then 24 percent of the observed height variation among individuals in the population in the next generation would disappear. To say, however, that 76 percent of Evelyn Fox Keller’s height was caused by her genes and 24 percent by her nutrition does not make sense. The nonsensical implication of trying to partition the causes of her individual height would be that if she never ate anything she would still be three quarters as tall as she is.
- Keller is too optimistic about the assignment of causes of variation even when considering variation in a population. As she herself notes parenthetically, the assignment of relative proportions of population variation to different causes in a population depends on there being no specific interaction between the causes. She gives as a simple example the sound of two different drummers playing at a distance from us. If each drummer plays each drum for us, we should be able to tell the effect of different drummers as opposed to differences between drums. But she admits that is only true if the drummers themselves do not change their ways of playing when they change drums.
- If there are several variable factors influencing some phenomenon, how are we to assign the relative importance to each in determining total variation?
- Suppose that we plant seeds of each of two different varieties of corn in two different locations with the following results measured in bushels of corn produced (see Table 1).
  
  There are differences between the varieties in their yield from location to location and there are differences between locations from variety to variety. So, both variety and location matter. But there is no average variation between locations when averaged over varieties or between varieties when averaged over locations. Just by knowing the variation in yield associated with location and variety separately does not tell us which factor is the more important source of variation; nor do the facts of location and variety exhaust the description of that variation.
- There is a third source of variation called the “interaction,” the variation that cannot be accounted for simply by the separate average effects of location and variety. There is no difference that appears between the average of different varieties or average of different locations, suggesting that neither location or variety matters to yield. Yet the yields of corn were different when different particular combinations of variety and location are observed. These effects of particular combinations of factors, not accounted for by the average effects of each factor separately, are thrown into an unanalyzed category called “interaction” with no concrete physical model made explicit.
- The Mirage of a Space Between Nature and Nurture appears in an era when biological—and specifically, genetic—causation is taken as the preferred explanation for all human physical differences. Although the early and mid-twentieth century was a period of immense popularity of genetic explanations for class and race differences in mental ability and temperament, especially among social scientists, such theories have now virtually disappeared from public view
- Ironically, at the same time that genetics has ceased to be a popular explanation for human intellectual and temperamental differences, genetic theories for the causation of virtually every physical disorder have become the mode.
- DNA studies of disease causation had a “relatively low impact.” Both of these articles were instigated by several articles in The New England Journal of Medicine, which had come to the conclusion that the search for genes underlying common causes of mortality had so far yielded virtually nothing useful. The failure to find such genes continues and it seems likely that the search for the genes causing most common diseases will go the way of the search for the genes for IQ.
- A major problem in understanding what geneticists have found out about the relation between genes and manifest characteristics of organisms is an overly flexible use of language that creates ambiguities of meaning. In particular, their use of the terms “heritable” and “heritability” is so confusing
- When a biological characteristic is said to be “heritable,” it means that it is capable of being transmitted from parents to offspring, just as money may be inherited, although neither is inevitable. In contrast, “heritability” is a statistical concept, the proportion of variation of a characteristic in a population that is attributable to genetic variation among individuals. The implication of “heritability” is that some proportion of the next generation will possess it.
- The move from “heritable” to “heritability” is a switch from a qualitative property at the level of an individual to a statistical characterization of a population. Of course, to have a nonzero heritability in a population, a trait must be heritable at the individual level. But it is important to note that even a trait that is perfectly heritable at the individual level might have essentially zero heritability at the population level. If I possess a unique genetic variant that enables me with no effort at all to perform a task that many other people have learned to do only after great effort, then that ability is heritable in me and may possibly be passed on to my children, but it may also be of zero heritability in the population.
- One of the problems of exploring an intellectual discipline from the outside is that the importance of certain basic methodological considerations is not always apparent to the observer, considerations that mold the entire intellectual structure that characterizes the field. So, in her first chapter, “Nature and Nurture as Alternatives,” Fox Keller writes that “my concern is with the tendency to think of nature and nurture as separable and hence as comparable, as forces to which relative strength can be assigned.” That concern is entirely appropriate for an external critic, and especially one who, like Fox Keller, comes from theoretical physics rather than experimental biology. Experimental geneticists, however, find environmental effects a serious distraction from the study of genetic and molecular mechanisms that are at the center of their interest, so they do their best to work with cases in which environmental effects are at a minimum or in which those effects can be manipulated at will. If the machine model of organisms that underlies our entire approach to the study of biology is to work for us, we must restrict our objects of study to those in which we can observe and manipulate all the gears and levers
- Genetics, from its very beginning, has been a “subtractive” science. That is, it is based on the analysis of the difference between natural or “wild-type” organisms and those with some genetic defect that may interfere in some observable way with regular function. But to carry out such comparison it is necessary that the organisms being studied are, to the extent possible, identical in all other respects, and that the comparison is carried out in an environment that does not, itself, generate atypical responses yet allows the possible effect of the genetic perturbation to be observed. We must face the possibility that such a subtractive approach will never be able to reveal the way in which nature and nurture interact in normal circumstances.
- An alternative to the standard subtractive method of genetic perturbations would be a synthetic approach in which living systems would be constructed ab initio from their molecular elements. It is now clear that most of the DNA in an organism is not contained in genes in the usual sense.
- 98–99 percent of the DNA is not a code for a sequence of amino acids that will be assembled into long chains that will fold up to become the proteins that are essential to the formation of organisms; yet that nongenic DNA is transmitted faithfully from generation to generation just like the genic DNA.

Jun

2011

Analysis: Hold the panic on cell phones and cancer | Phones | iOS Central | Macworld

Do cell phones cause cancer? Nobody really knows for sure, but scientists are determined to keep an eye on the ever-evolving evidence that continues to accumulate on the subject.

That’s the gist of a report recently released by the World Health Organization’s International Agency for Research on Cancer (IARC), the United Nations body responsible for oncological studies. In the report, IARC scientists have classified cell phone usage as a possible cause of cancer, meaning that, while the data currently available is still inconclusive, the subject deserves further research before a call can be made one way or another.

www.macworld.com/...phone_cancer_who_analysis.html

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Mobile Wi-Fi Radio Waves Cancer Uncertainty Causation Model

Today’s cell phones are, essentially, extremely sophisticated radios and, as such, emit electromagnetic waves. Much like the vast majority of radiation that surrounds us—from visible light to AM and FM radio waves—electromagnetic waves do not possess enough energy to interact directly with the tissues in our bodies in a way that can cause direct damage.

“The radiation that cell phones emit is nowhere near the kind of radiation that x-ray machines, for example, emit,” says Perras. “X-rays […] have much, much shorter wavelengths. Consequently, [they] carry much more energy and thus have much more penetrating power, which is required to be able to image the interior of the human body.”
X-rays and other “hard” waves are called ionizing radiation because they can interact with the human body in a way that leads to the creation of chemical compounds called free radicals that can, in turn, be responsible for mutations and the incidence of cancer.
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- The focus of much of the currently-ongoing scientific research, then, is on whether the radiation emitted by cell phones is focused enough to be absorbed into the body and cause heating, which could, in the long run, damage human tissue and eventually lead to cancer.
- The issue is particularly important because most users still hold their phones close to the head; since the brain is particularly sensitive to external stimuli, even a small amount of heat could lead to medical trouble in the long term.
- What makes it challenging to determine if a link between cell phones and cancer actually exists are the many variables involved. “The incidence of brain tumors is quite small, making it more difficult to study in large numbers,” says Dr. Eric Olyejar, a Radiation Oncologist from Ironwood Cancer and Research Centers, based in Chandler, Ariz. That means “quantifying the lifetime dose each patient received is extremely difficult.”
- To make things more difficult, cancer often develops as a result of many different factors. “Family history, exposure to chemicals or radiation, growth defects, the amount of radiation that is actually coming from the phone, amount of time used, proximity to the brain, skull thickness, and wave frequency are only a few of the many variables,” Olyejar says.
- cell phones have become so ubiquitous that it’s hard to compare the health of users and non-users.