- Atheism 101

Evidence - "A thing or things helpful in forming a conclusion or judgment" Dictionary.com

Overview

The question of evidence and what constitutes acceptable evidence rises throughout this site.

There are two important factors effecting the validity of evidence:

Quality
Quantity

The Quality of Evidence is determined by the degree to which it is:

Reproducible
Testable
Verifiable

The Quantity of Evidence looks at how many different pieces of evidence, as well as, how many different forms of evidence are pointing in the same direction.

I'll actually apply these concepts in the Crime Scene Analogy below as well as provide a real world application of these principles in the Real World Example: The Alleged Ossuary of James below. Finally, I will provide a list of Valid Evidence and Less than Valid Evidence when discussing the topics in this site. (I use the term "Less than Valid" because no evidence is totally invalid unless it is forged, faked, etc.)

In a more detailed look at the topic of evidence there are two components which I think are important to establish - Quality and Quantity.

Quality involves the source of the evidence. Is it from a scholar in the field, or someone's Aunt Sally? An extreme example, but you see what I mean. The quality of a form of evidence can also be determined by the degree to which the evidence is: testable, reproducible and verifiable. A more detailed look at these concepts is discussed in the Quality of Evidence section below.

Quanity involves the amount of evidence pointing in the same direction. In the analogy below you can see that the more pieces of evidence pointing to the same conclusion - the stronger the conviction that the conclusion is probably correct.

Is evidence proof? No. There is very little "proof" in the world. As our technology increases and our knowledge grows there is always room for more information. 500 years ago people in Europe were certain the Earth was flat. We have now learned otherwise.

With that said let's look at a specific analogy.

Crime Scene Analogy:

I often think of the search for God as a murder mystery. When you arrive at the scene, the victim is dead. The murderer is not present and the actual crime is rarely witnessed. However, it is sometimes possible to deduce when the crime happened, how it happened, where it happened and who the murderer is by evidence left at the scene.

There are many kinds of evidence and those various kinds carry different weights as to their validity and believability. Let's review some typical types of evidence at the scene of a crime:

Eyewitness Testimony
Murder weapon
DNA
Fingerprints

Now let's examine the reliability of the various kinds of evidence:

1. Eyewitness Testimony

This is probably the most unreliable type of evidence listed. Why? Human senses are easily fooled. Think about it. If you were a prosecuting attorney, would you rather have eyewitness testimony that put the murderer at the scene of the crime or DNA and fingerprints? Eyewitnesses are easily disproven. They can be older people whose eyesight and/or hearing is not what it used to be. It could have been dark or noisy and prevented an accurate perception of the events. The witness could have been distracted, or drunk, or high, or simply prejudicial to a certain point of view. They might also be mentally ill. It is also possible that their perception has bee tainted by the police or by hearing the testimony of other witnesses.

Have you ever thought you had a fever only to be disproven by the thermometer? Or did you think it was cold enough to snow today only to be disproven by the weather report? Have you ever thought you heard something that you did not hear? Or missed seeing something that was right in front of your face? Human senses are not always accurate or reliable.

2. Murder Weapon

More tangible and concrete than eyewitness testimony, the murder weapon is a better form of evidence. Why? Because it can be observed and judged by everyone. It can be tested for fingerprints or blood. It can be traced to find ownership records. However, the mere existence of the murder weapon is not conclusive proof of who actually used the weapon. Without DNA or fingerprints it's hard to link this inanimate object with the human that actually held it.

DNA

With a 99.9% reliability rate DNA is a much more conclusive form of evidence. We can link a murder weapon, a victim or a scene with a human body. If a person's DNA is present on, say, a murder weapon

Fingerprints

Fingerprints also have a high reliability rate. No two humans have the same fingerprints. So if we can show that a defendant's fingerprints are present, we can put them in the presence of that object at some time.

With this analogy in mind, let's return to our discussion of evidence.

What makes some evidence better than others? There are two major factors when considering the validity of evidence: Quanity and Quality. Let's look at Quality first.

Quality of Evidence

The quality of any form of evidence can be determined by the degree to which it is Testable, Verifiable and Reproducible.

1) Testable
The court is not expected to take the prosecuting attorney's word that the DNA evidence implicates the defendant. His claim that the blood found at the scene is the same blood as that of the defendant is easily testable in any lab. It is not a matter of his opinion, but of objective, documented testing methods agreed upon beforehand by both parties in the case.

2) Reproducible
If the prosecuting attorney claims that blood gathered at the scene was tested and found to be consistent with the DNA of the defendant, BUT, the blood was lost and cannot be retested by the defense, then the evidence comes into question. The tests are no longer reproducible.

3) Verifiable
If the prosecuting attorney claims that blood gathered at the scene was tested and is that of the defendant, BUT the defense attorney has the same tests conducted and comes up with different results, then the evidence also loses validity. Evidence must be verifiable by many different parties conducting the same tests to be conclusive.

The same thing holds true for fingerprints. If the prosecuting attorney claims the defendant's prints are all over the crime scene, this statement is easily tested. If the prints taken at the crime scene are lost then the claim is no longer valid. Why? Because the claim is no longer testable, reproducible or verifiable. So this evidence no longer constitutes reliable evidence.

Does this mean that the prosecuting attorney will throw out any evidence that does not meet these three requirements? Obviously not. But the validity of the case is directly proportionate to the quality and quantity of the evidence gathered. For instance, two murders are committed.

At the first murder scene the police find:

1. Three eyewitness that can place a person who matches the defendant's description at the scene of the crime. The witnesses are upstanding members of the community, in their mid-thirties. They have no sight or hearing impairments. They are not intoxicated or on any illegal substances at the time of the incident. The murder occurred at noon on a bright sunny day.
No other evidence is found placing the defendant at the scene.

At the second crime scene the police find:

1. No eyewitnesses.
2. The fingerprints of the defendant in the victim's blood on several items in the room.
3. Blood at the scene that matches the DNA of the defendant.

Which case would you rather prosecute? Which defendant would you rather defend?

Scores of people have been imprisoned on eyewitness testimony that were later found to be innocent through DNA testing. Several of them have been put on death row by juries that were that certain of the eyewitness testimony they heard. Yet they were wrong.

Does this mean that all eyewitness testimony is wrong? Does it mean that all eyewitness testimony is invalid? No. That is not the point of this section at all. The point I am trying to make is that eyewitness testimony is the least reliable form of evidence.

Quantity

Now let's look at the component of Quality when considering evidence. The more different kinds of evidence you have pointing to the same conclusion, the more likely it is that the conclusion is true. Please notice that I said different "kinds" of evidence. What do I mean by that? Let's continue with the crime scene analogy. Again you have two crime scenes where a murder has taken place.

In the first case the police find:

1. The blood type of the victim on the defendant's hands.
2. The blood type of the victim on the defendant's shoes.
3. The blood type of the victim on the defendant's clothes.
4. The blood type of the victim in the defendant's car.
5. The blood type of the victim in the defendant's hair.
6. The blood type of the victim in the defendant's home.

In the second case the police find:

1. Hair that appears microscopically identical the same as the defendant's in the victim's home.
2. The murder weapon in the defendant's home.
3. The defendant's fingerprints in the victim's home.
4. Skin of the same blood type as the defendant's under the victim's fingernails.

Two cases. Six pieces of evidence in the first case, only four in the second. In which case is the guilt of the defendant more likely? Well this section is discussing the quantity of evidence so it must be the first, right? Wrong. Did you catch it? Let's look.

The quality of the evidence increases when there are different kinds of evidence all pointing in the same direction. In the first case we only have the victim's blood type. The victim's blood seems to be everywhere, but it still constitutes only one type of evidence. It is feasible that the defendant ran into the victim's house, discovered the bloody scene and the victim's already murdered body, ran back out and went home. This would explain all of the blood evidence and not produce a murderer. Therefore it's fairly easy to dismiss only one kind of evidence.

Now let's look at the second scene. Hair evidence is not conclusive either. Many different people can have hair that is microscopally identical. How do we "know" it's the murder weapon? Fingerprints are a bit more conclusive. And with 4., once again, we are using blood type which is not conclusive. However, we now have four different kinds of evidence pointing at the same defendant. Can you devise a logical scenario that would explain how all four pieces of evidence could be present and yet the defendant still be innocent? It's much more difficult, right?

That is what I mean by the quantity of evidence. Obviously the quality must be considered as well. Neither factor alone constitutes conclusive evidence. However, the higher the quality of the evidence and the higher the quantity of different kinds of evidence the more likely the conclusion is correct.

Now let's return to the topic we were discussing previously. You can either return to the previous page by hitting the Back button on your browser, or by choosing one of the topics below:

Real World Example: The Alleged Ossuary of James

Here is a perfect example of a recent discovery and the types of evidence involved in discussing its merit. Let's look at the evidence submitted and its value.

Article in the Biblical Archaeology Review: A well renowned scholarly journal. It does have a point of view to consider (proving the Bible is true archaeologically), but appears without reproach.
Statements by Hershel Shanks, editor of the BAR and eyewitness: I am unable to determine his educational background, but he appears to be a well-respected scholar in the field.
Statements from the owner of the ossuary Oded Golan: A 51-year-old engineer from Tel Aviv who collects antiquities. Mr. Golan's story has changed several times regarding the acquisition of the ossuary. He is also under investigation by the Israeli authorities for black market dealings. A questionable source.
Opinions of André Lemaire: A noted paleographer of the École Pratique des Hautes Études (popularly known as the Sorbonne University) in Paris
Laboratory tests performed by the Geological Survey of Israel "confirm that the box’s limestone comes from the Jerusalem area. The patina--a thin sheen or covering that forms on stone and other materials over time--has the cauliflower-type shape known to develop in a cave environment; more importantly, it shows no trace of modern elements". (from the Biblical Archaeology Review): Laboratory tests are easily verifiable and reproducible. The Geological Survey of Israel appears without reproach.
Opinions of Rochelle Altman: An expert on scripts and an historian of writing systems, also without reproach.

An excellent summary of the current status of the investigations, as well as an overview of the key players and their various positions is given by Paul Flescher, Director of the Religious Studies program at the University of Wyoming in his article, "The Experts and the Ossuary".

If anyone has additional information regarding these sources or others please contact me.

One final issue to be addressed is evidence vs. proof.

Evidence vs. Proof

Is evidence ever infallible? No. Evidence is not proof. Evidence consists of pieces of information that lead us to the truth. The better the evidence, the more evidence we accumulate, the more certain we can be that we are close to the truth. However, it is rare to have enough evidence to say something has been proven.

Think about the O.J. Simpson case. Tons of evidence were present; DNA, shoe prints, blood types, possible murder weapon. But do you know for a fact that he did it? With the amount of evidence and the quality of the evidence we can feel pretty certain that we know he did it. But it has not been proven beyond a doubt. Evidence is not proof. No one can say that it was proven that O.J. did it.

However, with the quality and quantity of evidence found at the scene and at O.J.'s home most of us feel fairly certain that the guilt of O.J. Simpson is extremely close to the truth.

Evidence when Discussing God, Atheism, Evolution, etc.

With all of these said, what then would constitute valid evidence in discussions involving God, atheism, evolution, etc.? Evidence is certainly not limited to items listed below, but hopefully these will give people a good idea of what does and does not constitute valid evidence.

Examples of Valid Evidence

Examples of valid evidence would include:

Articles in scientific journals

Scientific journals are published for the purpose of describing how evidence was obtained so that others in the field can make their own tests and see if they too obtain the same results. If different results are obtained, these too are published in the same journals. The purpose of scientific journals is to put the evidence on the table for examination and criticism by one's peers. For these reasons articles in scientific journals are considered valid evidence.

Articles in scholastic journals

As with scientific journals these journals also provide an open forum for presenting ideas and evidence for scrutiny by one's peers and are therefore included.

Articles on the Internet by scholars in the field

When documented as to the source of the article and the background of the scholar these sources are also valid. It is important to note that a scholar is typically someone with an educational background in the same field as the one on which they are commenting. Though this would seem obvious to most there are those who seem unaware of it, so I mention it here.

News articles quoting scholars in the field or citing works of research or discoveries

Obviously the opinions of Ted Koppel on Brane Theory are not as valid as those of Stephen Hawking. It is important to know whose views are being presented in any given article.

At this writing I am certain there are forms of evidence which I have not yet though of so submissions are not limited to those above.

Examples of Less Than Valid Evidence

And what is not considered a conclusive form of evidence?

Personal experience, see the Analogy above and the discussion on eyewitness testimony
"The Bible says" see the detailed discussion on the Bible
"My pastor says", unless of course your pastor is a scholar in the field for which you are providing evidence
"There was a man who...", urban legends and hearsay do not constitute conclusive evidence

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