Whaddaya Know?

A traditional religious Jew claims to "know" that the Torah is the revealed word of the one God.

A traditional religious Catholic claims to "know" that the Eucharist is really, truly and objectively the body and blood of Christ.

A traditional religious Muslim claims to "know" that angels exist as incorporeal beings, including the three main angels, Jibril, Israfil, and Azrail.

A religious Mormon claims to "know" that Jesus Christ appeared to Native Americans in North America after his crucifixion at Golgotha.

None of these things constitute knowledge. In fact, none of them is true, but that's a subject for future posts. This post is about the nature of knowledge.

I started to write a short post on what it means so say that "I know" or that "we know" something. But it turned into a long post. So I've put it on a separate web page here. The capsule summary is:

• We know nothing about the real world with certainty. (We can know mathematical truths with certainty, but only because they are truths about objects that we have ourselves defined, and whose properties we have specified. Such truths - e.g. that there are an infinitude of prime numbers - are not about objects in the physical world.)
• The scientific method is the best - indeed, really the only - objective way that we have developed to gain knowledge about the real world.
• There is no subjective way.
• The scientific method enables us to disprove conclusively hypotheses about the nature of reality. It does not enable us to prove them, but it does allow us to know with very high probability what is true.
• More importantly, the scientific method enables us to put constraints around what might possibly be true. Thus, if you have a new theory of gravity, it must conform to all the accurate observations made to date about how gravity behaves.
• Useful hypotheses make unambiguous predictions that can be tested.

There are other ways people use for "knowing". They include:

• Introspection. This may be a way of knowing about your own inner state (although it turns out to be a very poor way; see this classic paper on social psychology.) Absent further advances in neurobiology, it may be the only way. But it is not a valid way to gain knowledge about the external world.
• Authority. This simply reduces the question to one of how the authority claims knowledge, and how accurately you understand and represent the authority.
• Revelation. This is, I contend, self-deception at best, and psychosis at worst. After all, people claim certain knowledge through revelation of many things such as different religious "truths" that are inconsistent with one another. At most one of them could be correct. In any case, if knowledge obtained via revelation can be tested, then you are actually using the scientific method to know. If it cannot be tested, then it is not knowledge.

For details I refer you to the long post. Let's review the four pieces of claimed knowledge that I cited at the beginning of this post.

The claim that the Torah is the revealed word of the one God is a claim based on authority - rabbinical authority in this case. There is no direct evidence for this claim. Indeed, there are so many internal contradictions in the Torah (order of creation in Genesis 1 vs. Genesis 2, number of animals taken on Noah's Ark in Genesis 6:19 vs. Genesis 7:2, etc.) that there could not be such evidence unless God made some mistakes.

The claim that the Eucharist is the body and blood of Christ is based on papal authority, which is based on papal interpretations of the gospels. In so far as it has been tested (by chemical analysis of the wafer and wine) it is, of course, false. If the claim is that The Eucharist is the body and blood of Christ in some other-than-physical way (see this article for a discussion) then it's not testable, and perhaps not meaningful.

The claim that angels, and those three angels in particular, exist as incorporeal beings is a claim to the authority of the Qur'an, which in turn is a claim via revelation of the Qur'an to Mohammed. It's not clear that it's testable.

The claim that Jesus visited North America after his crucifixion is based on revelation to Joseph Smith. To the extent that it can be tested via archaeological evidence, none has been found. It's not clear that it's testable.

So none of these constitute knowledge as I use the term.

I'll end with a quote from Stephen Jay Gould:

In science, "fact" can only mean "confirmed to such a degree that it would be perverse to withhold provisional assent." I suppose that apples might start to rise tomorrow, but the possibility does not merit equal time in physics classrooms.

About this blog

In this blog I'm going to examine various theologies with a critical eye. I'm motivated by a question, a heartfelt feeling, and a conviction. The question is simple: "What's true?" That is, what is the true nature of the universe in which we live? The feeling is one of profound dismay, at seeing so many people, including many intelligent people, who believe things about reality that seem to me to be such patent nonsense. The conviction is that this matters. That is, the fact that so much of humanity believes impossible things poses a great obstacle to a better world, and - as everyone should know in the post-9/11 era - a profound danger as well.

To make my case, I'm going to address each theology on its own merits (or lack thereof.) I have no intention of making a general argument against the existence of God, since that word has no uniform definition. One can make a careful, scientific argument against the existence of a God with certain specified attributes, and Victor Stenger's book does a fine job of that. But part of my aim is to review the details of what people of different religions purport to believe. So I'm going to examine those beliefs case by case.

Let me make a couple of points to clarify my intentions:

• First, I distinguish theology from religion. Most religions include a theology, but they also typically have at least two other important elements: a set of rituals and traditions, and a code of ethics that describe how one ought to behave. These two elements are not divorced from the religion's theology, but - as I hope to make clear in subsequent discussions - in practice they are rather distinct. Except as they reflect on a religion's theology, I will generally avoid discussing the rituals and ethical teachings of religions.
• Second, I'm an atheist, as should be obvious by now. I don't see much difference between believing in God and believing in Santa Claus. But I'm determined to do my best to represent fairly each of the theologies that I discuss. If you believe that I misrepresent the theological teachings of some religion under discussion, please let me know.

Here's a very well-known example of my argument: traditional Judaism teaches that the Torah, the first five books of the Hebrew Bible, is the literal word of God, as dictated to Moses. The Torah includes both history (such as the creation stories in Genesis, the story of Noah and the flood, and the story of the flight of the Hebrews from Egypt) and laws of behavior (such as the 10 commandments, the dietary laws, and the Holiness Code.) Traditional Jews hold it to be true in every aspect. But in addition to the internal contradictions, such as the different order of creation between Genesis 1 and Genesis 2, there are stories that we know to be historically false. For example, Genesis chapters 6 through 9 tell the story of the great flood. But there has never been a global flood. See here for a list of some of the reasons why geologists know this. The literal truth of the Hebrew Bible, a core belief of traditional Judaism, is falsified by geology. Nothing new here. Traditional Christianity also claims that the Hebrew Bible (referred to by Christians as the Old Testament) is inerrant, so traditional, or fundamentalist, Christianity is also falsified. Nothing new here either.

(It's worth remarking that, when viewed as a metaphor, the flood story is quite wonderful, and this is true for many other parts of the Hebrew Bible and other scriptures. But since my concern in this blog is theology as a (mis-)description of reality, I will not generally address metaphorical interpretations unless the theology under discussion also uses such interpretations.)

Another, more contemporary example: the religion called Scientology describes a universe that is more than 10⁸⁵ years old. But cosmologists know that the universe is about 10¹⁰ years old. The Scientologist version of reality has been falsified by modern cosmology.

Most people in the word are religious. There are a variety of proposed explanations for this. Some, such as Dean Hamer, think the explanation is genetic. Others think that it is memetic. I don't plan to directly answer this question. I think that there are a number of reasons why people are religious, most of them having to do with the social psychology of human behavior. Religion provides you with an in-group. In most cases, it provides a means to assuage your fear of death. It provides canned answers to questions that people have wondered about for all of human existence. As an institution, religion seems to fulfill some deep-seated needs of human beings.

The trouble is, most religions claim to provide a description of the true nature of reality. And in essentially every case, we know enough about reality to know that those claims are false. Another simple example: ancient Greek theology stated that there were twelve deities - beings with supernatural powers - living atop Mount Olympus in Greece. Well, up above is a photo of Mount Olympus from space. Zoom in as much as you like; you're not going to find Zeus in the picture. And, of course, people have climbed Mount Olympus, and no gods are present, nor any evidence of their habitation. We know that Greek theology, as a description of reality, is false. And indeed, it has few if any adherents today; most likely you don't believe in Zeus.

If religion fulfills an essential human need, but all existing religions are - as I claim - false in their descriptions of reality, then how can we as humans get our needs met? This is a compelling question. Einstein said that the answer was through "striving after rational knowledge." I agree that this is the only way we can know anything about the true nature of reality, but rational knowledge by itself does not satisfy peoples' social needs for rituals and traditions, for reassurance and comfort, for a group to belong to, or - for that matter - for a group to disdain. The question of how secular people can get these needs met is not the main focus of this blog, but I will return to it from time to time in a suitable context.

As I said above, in future posts on this blog I'll discuss different theologies in turn, including those of both mainstream and more fringe religions. As they arise, I'll also discuss certain features common to multiple religions - such as the ideas of revelation, and of scripture. I'll tackle Judaism first, because it is my own tradition and because - despite being an atheist - I still identify as a Jew. Many of the issues in Jewish theology are also issues for the other major Abrahamic faiths, Christianity and Islam.

I also said above that we know enough about reality to evaluate many religious claims. It's worth spending a moment to discuss what I mean when I say we know something. Except for some mathematical propositions, we know nothing to be true with certainty. Einstein famously said "As far as the laws of mathematics refer to reality, they are not certain; and as far as they are certain, they do not refer to reality." All scientific knowledge is provisional, in the sense that it's always possible that a newly performed experiment will challenge our existing scientific laws. But in the year 2007 we are the beneficiaries of a program of conjecture, experiment and theory that has been carried out - by great geniuses and by more ordinary minds - over the course of more than two millennia. This is the program we call science. As a result, we can know some truths, if not with certainty, then with very great confidence.

For example, we understand a great deal about how gravity controls the motion of celestial objects, and we can test our understanding by making predictions. A solar eclipse was predicted for March 29, 2006, and as this article in the New York Times shows, it happened as predicted. Another solar eclipse is predicted for August 1, 2008. It is not absolutely certain that this will happen because (a) there could be some other, as yet unpredicted, celestial event that subtly changes the orbits of the earth or moon, or (b) there could be some subtle error in our understanding of gravity that causes us to make incorrect predictions. But (a) is extremely unlikely, and (b) is even more unlikely, given how successful our predictions have been in the past. In this sense, we know that a solar eclipse will take place next August 1.

What else do we know, how do we know it, and how does it bear on theology in general? More on that in my next post.