Necessary and sufficient conditions

The problem of finding definitions for things that clearly specify whether an object belongs in that category or not has long been recognized to be a knotty philosophical problem. Ideally what we would need for a good definition is to have both necessary and sufficient conditions, but it is not easy to do so.

A necessary condition is one that must be met if the object is to be considered even eligible for inclusion in the category. If an object meets this condition, then it is possible that it belongs in the category, but not certain. If it does not meet the condition, then we can definitely say that it does not belong. So necessary conditions for something can only classify objects into “maybe belongs” or “definitely does not belong.”

For example, let us try to define a dog. We might say that a necessary condition for some object to be considered as a possible dog is that it be a mammal. So if we know that something is a mammal, it might be a dog or it might be another kind of mammal, say a cat. But if something is not a mammal, then we know for sure it is not a dog.

A sufficient condition, on the other hand, acts differently. If an object meets the sufficient condition, then it definitely belongs. If it does not meet the sufficient condition, then it may or may not belong. So the sufficient condition can be used to classify things into “definitely belongs” or “maybe belongs.”

So for the dog case, if a dog has papers certified by the American Kennel Association, then we can definitely say it is a dog. But if something does not have such papers it may still be a dog (say a mixed breed) or it may not be a dog (it may be a table).

A satisfactory demarcation criterion would have both necessary and sufficient conditions because only then can we say of any given object that it either definitely belongs or it definitely does not belong. Usually these criteria take the form of a set of individually necessary conditions that, taken together, are sufficient. i.e., Each condition by itself is not sufficient but if all are met they become sufficient.

It is not easy to find such conditions, even for such a seemingly simple category as dogs, and that it the problem. So for the dog, we might try define it by saying that it is a mammal, with four legs, barks, etc. But people who are determined to challenge the criteria could find problems (What exactly defines a mammal? What is the difference between an arm and a leg? What constitutes a bark? Etc. We can end up in an infinite regression of definitions.)

This is why philosophers like to say that we make such identifications (“this is a dog, that is a cat”) based on an intuitive grasp of the idea of “similarity classes,” things that share similarities that may not be rigidly definable. So even a little child can arrive at a pretty good idea of what a dog is without formulating a strict definition, by encountering several dogs and being able to distinguish what separates dog-like qualities from non-dog like qualities. It is not completely fool proof. Once in a while we may come across a strange looking animal, some exotic breed that baffles us. But most times it is clear. We almost never mistake a cat for a dog, even though they share many characteristics, such as being small four-legged mammals with tails that are domestic pets.

Anyway, back to science, a satisfactory demarcation would require that we be able to find both necessary and sufficient criteria that can be used to define science, and use those conditions to separate ideas into science and non-science. Do such criteria exist? To answer that question we need to look at the history of science and see what are the common features that are shared by those bodies of knowledge we confidently call science.

This will be discussed in the next posting.

POST SCRIPT

I feel that the American media have not given nearly enough attention to the recently leaked secret and explosive “Downing Street memo” from the British secret service that reveals that Bush intended to invade Iraq all along and lied about it to the American people. Juan Cole says that the memo clearly reveals what has been long strongly suspected.

The Bush administration, and some credulous or loyal members of the press, have long tried to blame U.S. intelligence services for exaggerating the Iraq threat and thus misleading the president into going to war. That position was always weak, and it is now revealed as laughable. President Bush was not misled by shoddy intelligence. Rather, he insisted on getting the intelligence that would support the war on which he had already decided.

Cole’s article, where he lays out the sequence of events, is a must read.

The comparison with Darwin and ID

I am a bit of a veteran of the battles that have been waged by so-called intelligent design (ID) advocates to challenge science in general and the theory of evolution in particular. Although not a biologist, I have always had an interest in both physics and the underlying philosophy of science. In the mid-to-late 1990’s I was in the process of writing my first book Quest for Truth: Scientific Progress and Religious Beliefs (which was published in 2000), and it was towards the end of that period that the ID advocates started getting more vocal, at least in Ohio. I was initially drawn to the discussion because of their claim that ID was a scientific theory, which naturally raises the question of what makes a theory, any theory, scientific. As this was a central topic of my book, I looked into ID ideas, although not in any great depth at that time.
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Catholic and Protestant reactions to Darwin’s ideas

When reading and writing about the Copernican revolution and the religious opposition to it (see here, here, here, here, here, and here for that story in sequence), what immediately struck me were the similarities that that episode in scientific history had to the more recent religious opposition to Darwin’s ideas.

Edward Larson in his book Summer for the Gods from which he has published an extended excerpt points out that (in America at least) there was little formal opposition to Darwin’s ideas from the time of publication of Origin of Species in 1859 until about 1920 or so. (Opposition in England started much earlier and I will explore that question in a later posting.)

So as in the case of Copernicus, there was no religious opposition to a seminal work of science until about sixty years after its publication, and the initial religious opposition once again came from the Protestant camp. Initially, the fundamentalist Protestant movement was focused only on fighting “modernism” in the form of the so-called “higher criticism” which consists of “the study of the sources and literary methods employed by the biblical authors.” Such critical methods are not favored by the religious fundamentalists, who see the Bible as divinely inspired and infallible and thereby beyond any criticism. It was only later that Darwinism came to be included under the modernism umbrella.
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Creating the conditions for a just society – 3

According to John Rawls in his A Theory of Justice we have to get together once and for all and make the rules of operation without knowing our particular situation. (See here, here, and here for previous postings on this topic.) And once we make the rules, and then lift the veil of ignorance and find out our particular situation (our gender, age, abilities, skills, talents, health, community, position in society, wealth, income, educational qualifications, level of authority and power, etc.), we are not allowed to renegotiate to get more favorable terms for us. This restriction is important since it ensures that careful deliberation goes into making sure that the rules created are perceived as fair by all.

Let’s work through a specific simple case. People who are generally law-abiding would like to see laws and enforcement mechanisms that ensure their own safety and security and protect their property. If I belong to that category, I might want to advocate stern penalties (fines, imprisonment, harsh prison conditions, torture, even death) for law-breakers. But there is no guarantee that once the veil of ignorance is lifted, that I (for example) will be in the category of law-abiding people. It may turn out that I am actually a crook or have criminal intentions. Normally we would try and exclude crooks from the decision-making process because we have decided that they do not deserve the same rights as law-abiding people. But the veil of ignorance means that we cannot exclude people we disagree with in the rule-making process. I have to consider such possibilities as well when we agree to the rules.

So it is in my interest to make sure that the penalties for law-breaking are not too severe, since there is a chance that I may have to suffer them. Does this mean that crooks will prefer to opt for no penalties at all? No, because even crooks can function effectively only if they are the exception, if there is a general level of law-abiding behavior. After all, the executives who looted Enron and Tyco and caused thousands of people to lose all their savings could only do this because almost everyone else was behaving fairly honestly. This is why crooks can stash their stolen money in off-shore bank accounts and retrieve it later. If the officials in the off-shore banks were also crooks, the stolen money would not be ‘safe.’ Also if the other employees in your own company were not honest, the company would not make the amount of money that makes it worthwhile for you to steal it.

Even petty thieves could not function if everyone around them was also stealing from everyone else with no restriction. And since there is no guarantee that I will be the toughest crook around to fend off the other thieves, allowing for a totally lawless society could result in a terrible situation for me personally if it turns out (once the veil is lifted) that I am not very bright or strong or am clumsy with weapons. After all, there is no guarantee that I will be a skillful crook. An incompetent crook in a lawless society would fare much worse than one in a law-abiding society.

So it is in the interests of even crooks to create rules that encourage and reward honest behavior while ensuring reasonable treatment for law-breakers, just in case they get caught. So the two extremes (law abiding and honest people on the one hand, and crooks on the other) both have an interest in creating rules that balance the interests of both, since no one knows where they personally will end up.

What of the situation that triggered this series of posts, that of gay rights coming into conflict with certain interpretations of religions? Since the rules do not allow you to specify particulars, you cannot say (for example) that the Bible must be the basis for policy decisions. You would have to allow for the possibility for any religious text or that no religious text can form the basis. In other words, if the rules are to allow primacy for religion-based laws, you have to allow for the possibility that once the veil is lifted, you might end up as a Buddhist in a Judaism-based state or a Christian in a Hinduism-based state or you might be a gay person in an Islam-based state. If that should turn out to be the case, would you be content with the result?

Allowing for religious views to be the basis of regulating the private lives of individuals in a society also means allowing for the possibility that we might end up in a society run by groups like the now-defunct Shaker Christian sect, which advocated strict celibacy among its members. Of course, such a society would not likely last very long for obvious reasons (and the Shakers did, in fact, eventually disappear), but would we be willing to allow for this possibility?

Clearly the fact we could end up in any of these situations and have to live with it should cause us to think very carefully about what exactly are the rules of societal regulation that are important to us. I don’t know what specific resolution will be arrived at using the veil of ignorance to address the problem of gay rights and religious opposition to homosexuality. But what I am suggesting is that that is the way we have to address problems such as these if we are to not to just continue to talk through each other, simply asserting our preferences based on our situation and repeating the same arguments.

In some ways, what Rawls is suggesting is that we need to get in the habit of seeing what the world looks like through the eyes of others who may be quite different from us, and ask ourselves whether we would still see the world to as fair from that vantage point. It also requires us to think in terms of universal principles as opposed to principles based on the beliefs and practices of specific groups.

Thinking in this way is hard to do but needs to be done if we are to have any hope of overcoming the differences in policy preferences created by the huge diversity that exists amongst us.

Now clearly those who believe that their vision of God is the right one, and/or their particular religious or secular text is the only source of authority, are going to find it hard to deal with Rawls’ insistence that no identifiable and named groups can be used in formulating the rules. If you believe (for example) that Islam is the one true religion and that the Qu’ran (or Koran) has to be the basis of civil law, I cannot see how you can accept the ‘veil of ignorance’ principle (unless I am missing something). But rejecting this principle also means rejecting the idea of ‘justice as fairness,’ and dooms us to never-ending conflict because people who feel they are being unfairly treated will eventually rise up against their oppressors.

POST SCRIPT

There is an interesting article by Steven Pinker titled Sniffing out the Gay Gene that is well worth reading. I came across it in the excellent blog run by The Center for Genetics Research Ethics and Law.

Creating the conditions for a just society

The previous post that dealt with Dominionist’s negative views towards gays generated an interesting set of comments that frame nicely the kinds of problems we face when we try to arrive at rules for society that we can all live by and perceive as fair. (I will defer the planned posts on the religious opposition to Darwin to address this question first.)

In those comments, Joe’s understanding of Christianity leads him to think of homosexual behavior as sinful although he is not hostile to gays as people, drawing a parallel between the way that we can view alcoholism as bad while not thinking of alcoholics as evil people. Katie’s interpretation of Christianity, on the other hand, leads her to being a passionate supporter of gay rights. Aaron is an atheist, and Christianity-based arguments don’t have much sway with him. And, of course, there is a huge range of beliefs that span these three particular viewpoints. So how does one arrive at public policies that can be accepted as fair by everyone, not just with regard to gay rights, but in all aspects of public life?
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Dominionists and gays

Chris Hedges in his essay on the Dominionist movement in the May 2005 issue of Harper’s Magazine recalls something his ethics professor at Harvard Divinity School, Dr. James Luther Adams, told him twenty five years ago. Dr. Adams, who was eighty years old at that time, told Hedges that eventually he (Hedges) would be fighting “Christian fascists” who, he said “would not return wearing swastikas and brown shirts. Its ideological inheritors would cloak themselves in the language of the Bible; they would come carrying crosses and chanting the Pledge of Allegiance.”

Hedges continues: “Adams told us to watch closely the Christian right’s persecution of homosexuals and lesbians. Hitler, he reminded us, promised to restore moral values not long after he took power in 1933, then imposed a ban on all homosexual and lesbian organizations and publications…Homosexuals and lesbians, Adams said, would be the first “deviants” singled out by the Christian right. We would be the next.”

Was Adams being too gloomy? Was his comparison to Hitler overblown? Or was he remarkably prescient? It is hard to say. What is true is that homosexuality, like evolution, is high on the list of those things that are anathema to many religious believers, not just Christians. I have never been able to quite understand why it arouses such strong antipathy.

Take for example, all the referenda that were passed recently opposing same sex marriages. Much of the rhetoric warned that allowing gays to marry would take away from the sanctity of this institution. But we allow practically anyone to marry: murderers, rapists, pedophiles, criminals of any stripe, drug dealers, almost anybody with a pulse can marry with no restrictions whatsoever, and no one argues that this destroys the sanctity of marriage. Divorce is rampant, and yet no one is campaigning to have divorce outlawed in order to save the institution of marriage.

It is true that the Bible speaks out against homosexual behavior, but it also speaks out about a lot of things that do not get anywhere near the attention that homosexuality does. For example, homosexuality is not even one of the prohibitions cited in the Ten Commandments but adultery is. So, if someone is using the Bible as their main argument, surely for them adultery should rank worse than homosexuality and such people should also be campaigning for constitutional amendments against it?

Or is it that uniting against homosexuals is convenient because they are a minority and fairly defenseless politically? Historically, authoritarian movements have been able to unite the majority behind them by exploiting sentiment against small and powerless groups, by defining them as the “evil other.” But for this strategy to work, this “other” has to be fairly small numerically and “different.” It would be hard to mount a winning political campaign based on being against, for example, adultery. But by branding homosexuality as one of the worst forms of sexual “deviancy” it enables those who are not gay to feel very moral and superior, even though they themselves may be guilty of things that are actually harmful to others.

This is why I think that we should defend the right of gays to be treated the same way as anyone else, whether we ourselves are gay or not, or whether we even personally approve of the gay lifestyle or not. Gays are a powerless minority and the rights of powerless political minorities must be defended by all of us if we believe in a pluralistic society. Because in the end, each one of us can all be categorized as a minority is some way, and standing by while the equal rights of others are denied puts us all at risk.

Jews, Israel, and the Rapture

As pointed out earlier, believers in the Rapture are convinced that at the end of the world (which they think is imminent) all those people who are not Christians, or are even just nominal Christians and not the full-throttle version, are going to meet an extraordinarily sticky end, too gruesome for even a Quentin Tarantino or Mel Gibson film. But the role that Jews play in the rapture drama is curious and worth examining.

As Chris Hedges points out in his essay in the May 2005 issue of Harper’s Magazine, the Dominionist belief in the Rapture has a role for Jews that is not very appealing. They believe that “Israel must rule the Biblical land in order for Christ to return, though when he does, all Jews who do not convert to Christianity supposedly will be incinerated as the believers are lifted into heaven.”
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The Book of Revelations and the Rapture.

I am a huge fan of the English comic writer P. G. Wodehouse, especially of his Jeeves and Wooster books. These books are so funny that I have to literally wipe tears from my eyes. (Dave Barry has the same effect on me.) The plots are pretty much the same in all the Jeeves stories but the smoothness of Wodehouse’s writing, his superb comic touch, and his precise choice of words make them a joy to read. Even though I have read all of the Jeeves books many times and know all the plots by heart, I still re-read them periodically. Both Wodehouse and George Orwell had a command of the language that I admire.
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The changing media face of Christianity

I grew up in Sri Lanka in a family that worshipped in the Methodist Church. I was strongly influenced by my family and also by the minister in my church and the chaplain in the private Anglican (aka Episcopalian) school I attended. These priests had such an influence on me that I became quite religious and studied to become a lay minister in the Methodist church, and was ordained soon after I graduated from college.

In that capacity I would be sent to various churches on Sundays to conduct services. As a lay minister, I was authorized to run every aspect of the service except the communion. I was even invited me to go to theological college and become a full minister and I briefly, but seriously, considered the offer. But in the end, I decided that I really wanted to be a physicist and declined.
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David Horowitz and the art of the cheap shot

Oddly enough, just after posting two consecutive days on David Horowitz’s cheap shots against academics, yesterday I received the latest (May 6, 2005) issue of The Chronicle of Higher Education which featured a long cover story on him. (For someone who is constantly whining about not getting enough attention from academia, Horowitz seems to be extraordinarily successful in getting publications such as this to cover him and his ideas. See Michael Berube’s blog for a response.)
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