Monday, April 25, 2011

The Problem of Causation: An Introduction

Causation is the law of cause and effect.  When I strike a brick with a hammer and the brick breaks into pieces, we would say that the hammer’s blow caused the brick to break apart.  But it’s not always so easy to identify cause and effect.  Moreover, even in the above example, how do we know that it was the force of the hammer that caused the brick to crumble?  We make mental determinations that A caused B to happen many times each day-- taking causation for granted-- but on close inspection this concept proves to be much more complicated and problematic than it appears at first glance.  Let’s explore some different viewpoints in an attempt to reach a better understanding.  

Immanuel Kant was an 18th-century, German philosopher.  Picking up where Hume left off, Kant exposed the solipsistic speculation and logical fallacies that marred the works of many of Europe’s early modern philosophers, and his writings ushered in a new era in Western metaphysical thought.

In his Critique on Pure Reason, Kant includes Causality as one of his “categories” of pure understanding.  These are concepts which the mind uses to organize and make sense of the external universe taken in through the senses (what he would call “the manifold of phenomena”).  According to Kant, the categories are not something we gain through experience or sensory perception, but rather their origins lie in the mind itself (Kant used the term a priori, signifying that the categories-- or at least some kernel of them-- exist in the mind prior to any experience, but I think it might be better to say that their origins are independent of sensory perception).  This makes sense because we cannot perceive causation: we might observe that A takes place before B (or that A and B occur at the same time), but we must make a deductive leap in order to say that A causes B.  In our example, we see the hammer strike the brick and we see the brick smash into pieces, but saying that the hammer’s blow caused the brick to break requires a judgment on our part.


This might sound like the sort of abstract problem that only philosophers lose sleep over and that has no practical impact in our daily lives.  Indeed, when we’re talking about the brick smashing into pieces after it’s struck with a hammer, it doesn’t take much of a leap to say that the hammer was the cause of the smash.  This deduction is of the “common sense” variety, and it seems more unreasonable to deny the causal link than to accept it.  But it’s not always so simple: what about the documented correlation between gingivitis and heart disease?  What about a study that shows that gifted and talented children tend to be taller on average than their peers? or that there is a higher incidence of chemical dependency among the homeless?

It is a mantra among statisticians that correlation does not imply causation.  This is because when a statistically significant correlation is found between A and B it could mean  that (1) A causes B or (2) B causes A (did the people surveyed lose their homes because of chemical dependency or did they turn to drugs and alcohol because they were living on the streets?), or A and B could both be caused by other variable(s) (maybe those children are taller and smarter because their families are more affluent and they received better nutrition as infants), or maybe further studies will show that the apparent connection was just a coincidence after all.

Scientists normally deal in theories and evidence rather than laws or proof.  Thus it can almost never be conclusively proven by science that A causes B; normally, the best we can do is build a mound of convincing evidence-- by conducting more studies, experiments, surveys--  until  a general consensus is reached among the scientific community that A most probably causes B.  On the other hand, it is much easier to disprove a hypothetical or theoretical causal link: it often takes just one experiment, the results of which run contrary to what would be expected under the theory, in order to convince us that the theory should be abandoned.  20th-century philosopher Karl Popper calls this a logical asymmetry between verification and falsification lying at the heart of the philosophy of science.

Looking at the political debate currently surrounding the issue of climate change, one might argue that opponents of environmental legislation are exploiting this feature of the scientific method in order to cast doubt on the theory that human activity is causing the observed change in global temperatures despite a wealth of evidence and the theory’s widespread acceptance among the scientific community.


Returning to the theoretical, Kant states that we cannot directly observe cause and effect, and scientists recognize the difficulty in proving causation based on correlation, but some philosophical systems go even further.
Gottfried Wilhelm Leibniz was a pre-Kantian, German philosopher: today he is probably best known for being embroiled in controversy with Isaac Newton over who invented the calculus and perhaps as a leading exponent of philosophical optimism, which Voltaire skewered in his satire Candide (where that worldview is taught by the ridiculous Dr. Pangloss).

In his works on metaphysics, Leibniz imagined the universe to be composed of fundamental units, a lot like atoms but immaterial, which he called “monads.”  Physical objects are made up of monads, and a man’s soul is also a monad (Leibniz would say that the soul is simple, indivisible and immortal).  One of the more curious characteristics of monads is that each one reflects back the entire universe.  At some point in the Monadology, Leibniz makes the poetic if confusing claim that objects closest to the monad are reflected most clearly and in the most detail and that objects that are further removed in space (and time?) might be reflected less distinctly, but this does not contradict what is made explicit elsewhere… that each monad can show you all of creation.

Just as each cell in your body contains DNA instructions for building the entire organism, so we can think of monads as having within them code detailing not only their own characteristics and their personal past and future, but also their relationship with all the other monads populating the universe and (basically) God’s grand design.   

This quirky vision of the universe holds many implications.  First, since the past and the future are all written down in each monad’s “script,” it follows that everything that happens must be preordained and thus there can really be no free will in Leibniz’s universe.  Secondly, there is no true interaction between the monads and thus no causation (except in the sense that God causes everything to happen according to His plan).  When hammer strikes brick it may appear that the hammer causes the brick to smash, but really the monads comprising these two objects are just performing a choreographed ballet, each obeying the instructions written down in its own script, independent and untroubled by the actions of its fellow monads.    


If we turn now to Eastern Philosophy, one concept we’ll find that relates to cause and effect is that of karma.  In Sanskrit, karma means “action,” and the doctrine of karma-- closely tied to reincarnation and the cycle of birth and death-- is important in both Hinduism and Buddhism.  The law of karma is basically causation writ large: one’s actions have a ripple effect shaping  one’s life experiences in the present and into the future.  Good deeds have a positive impact, and bad actions affect one’s life negatively.

Reincarnation aside, this way of thinking about the world can be oddly attractive,  and many people instinctively embrace it on some level (more on this in a later post).  Part of its appeal might be that karma tells us that our future is to a large extent shaped by our own actions and choices rather than being predetermined by fate or decided by factors beyond our control.  It also suggests a cosmos ordered by justice where sooner or later evil will be punished and virtue will find its reward.  Moreover, karma is an extension of what we can observe and deduce on a smaller scale.  If a person is miserable, walks around with a scowl on his face and is nasty to the people he interacts with, he’s bound to spread negativity among his family, friends, coworkers and the community he lives in.  Thus the people around him are more likely to be miserable and nasty to others and chances are good that this negativity will be reflected back on him.  On the other hand, if one is cheerful and smiles and is kind to people one will spread joy throughout the community and this increased joy is likely to make his experiences more positive.


Another Buddhist concept which deals in cause and effect is that which is called pratitya-samutpada in Sanskrit or paticcasamuppada in Pali.  It has been rendered in English as “dependent co-arising” or “interdependent arising.”  It’s not easy to wrap one’s head around, but the doctrine basically states that everything in the universe lacks permanence and inherent reality; on the contrary, its existence is conditional and due to the confluence of a variety of different causes. Vietnamese  Zen Master Thich Nhat Hanh uses the example of a chair to explain this: the chair wouldn’t exist were it not for the wood it’s made of, the carpenter who crafted it, the tools he used, etc.  An object’s root causes are in turn conditional and owe their existence to other causes.

Paticcasamuppada has implications on a number of different levels.  First, it is an explanation for how the world came into existence without a creator: things co-arise and their existence is owing to a web of interdependent cause and effect relationships.  On a more practical level, it also includes the notion that our mind participates in the creation of our “reality.”  A lot of what we experience and accept as real is actually created or shaped by our thoughts and emotions-- the grasping desires or aversion of the ego,  the stories we create in our head (regarding other people’s motives or impressions of us, for example), etc.  Whether our viewpoint is helpful or unhelpful, correct or incorrect will make a big difference in how we experience the world.

Thirdly, central to “dependent co-arising” is an awareness that everything we perceive-- not only phenomena and objects in the external world, but even our own bodies, minds and inner most selves -- lacks permanence and inherent reality. On the contrary, all is fundamentally empty, and its existence is dependent on a number of external causes. 

As secular Westerners and intellectuals we tend to strongly self-identify with the mind; indeed, in his Mediations on First Philosophy, Rene Descartes-- regarded as the father of modern European philosophy-- famously declared as his first certainty “cogito ergo sum” (“I think therefore I am”).  Thus we rarely question the reality and the integrity of our own minds.  Nevertheless, psychologists and Buddhist monks alike will tell you that a lot of the thoughts and emotions that we include in this aggregate called “mind” have root causes in the genes we inherited, childhood traumas, good and bad lessons learned from our parents, crap we picked up from society…. The advanced Buddhist teaching of anatta or “no self” goes one step further and even denies the inherent existence of the atman as described in the Hindu Upanishads: the innermost self as observer.  Simply put, anatta states that when you peel away everything that is not the self you realize that you are left with nothing.

Thus, I would say that paticcasamuppada might lead one to the conclusion that reality is relative.  And if the inherent reality of the mind and the material world that surrounds us is called into doubt, then  perhaps this reduces the gap separating the visible from the invisible.  If we accept that familiar objects are all in some way empty, than it becomes difficult to distinguish them from more alien concepts such as karma, reincarnation, other planes of existence, an omni-pervasive God or “Buddha-nature,” even the fantastical tantric deities used by Tibetan Buddhists in their meditation practice-- maybe the difference between the reality of the material and the immaterial (what some would call imaginary) is only a matter of degree.

Image of Immanuel Kant is from anonymous portrait said to be dated c.1790 and was found at  Image of G W Leibniz is from c.1700 portrait by Bernhard Christoph Francke on display at the Herzog Anton Ulrich Museum in Braunschweig and was found on University of Houston/Leibniz Society of North America webpage; photograph of Reclining Buddha, Wat Pho, Bangkok, Thailand taken by Meeg on July 4, 2007.