Absence of Evidence

“Absence of evidence is not evidence of absence.”

• Martin Rees, a British astrophysicist and cosmologist

Absence of Evidence

Imagine you’re looking for your keys, and you think you might have left them on the bookshelf.  But when you look, you see nothing but books.  A natural conclusion to draw is that the keys are not there.

Now, imagine you’re an early 20th-century astrophysicist seeking to test the hypothesis that there is a planet (Vulcan) causing perturbations in Mercury’s orbit.  You keep looking but find nothing.  You conclude that Vulcan does not exist.

Both arguments seem straightforward, yet in both cases, you are relying on the assumption that an absence of evidence can be a good reason for inferring that what you are looking for is just not there.

In other words, an absence of evidence is evidence of absence.

But the opposite assumption — that an absence of evidence is not evidence of absence — has come to have the status of a received truth.

Absence of Evidence Fallacy?

“Absence of evidence does not mean evidence of absence” can be simplified to mean that the lack of evidence for the existence of something does not necessarily prove that it does not exist at all.

The absence of evidence can occur in a few ways.

For instance, someone could say that because there is no evidence for a position, that position must be false.  Or, someone could say that because the evidence against a position was recently disproven, the position must be correct after all.  You get the idea.

In other words, the absence of evidence fallacy occurs when someone uses a lack of evidence to try to “prove” something.

Of course, the problem with this line of reasoning is that a lack of evidence is just that: a lack.  You can’t use it to conclude anything; you could only conclude that we still don’t know anything.

The Bible

We see the absence of evidence fallacy show up in many places.

As an example, Brett contends he is not Spiderman but is quick to point out that no one has ever seen both he and Spiderman in the same room at the same time  So. . . .

If you fall for the fallacy, then you are susceptible to at least wonder about Brett.

The absence of evidence fallacy has been attempted to be used against the existence of God – which provides us a great primer into understanding the evidence of evidence fallacy.

Evidence

The “absence of evidence” acknowledges that there is a definition of evidence that is looked for that will determine whether something is true or not.  Seeing keys on the bookshelf  is good, undisputable “evidence.”

When it comes to the discussion about the existence of God, physically seeing him is usually the evidence looked for and not found – resulting in the claim that God doesn’t exist.

For us believers, we start with the Apostle Paul’s approach to the existence of God.

In Romans 1:20, he wrote,

For since the creation of the world God’s invisible qualities—his eternal power and divine nature—have been clearly seen, being understood from what has been made, so that people are without excuse.

His logic was that the Creator must be at least as powerful, magnificent, and complex as the universe he created (but more so), and these attributes are visible to all who live in this world.

Paul could see the stars, the vastness of space, and the immense power displayed in the cosmos.  So, he knew the Creator must be infinite, eternal, and immensely powerful or omnipotent.

And he could see nature with its beauty and complex biological life, including intelligent beings living on the earth.  So, God must be exceedingly intelligent.

Therefore, our evidence “evidence” of the existence of God is:

1. that the world had a beginning, and someone had to be there at the beginning that was an uncreated being, to start everything
2. the universe is infinitely complex yet ordered, and that could not have happened by chance
3. our biological complexity reveals an intelligent design that could only come from a god-type being
4. we are constantly enthralled with beauty, which can only be attributed to a higher power with an appreciation for each individual creature
5. we as humans are clearly set apart for a special place in our world
6. Finally, this is detailed explicitly in one book called The Bible.

The existence of God does not fall for the “existence of evidence fallacy” because there is ample evidence; it’s just not your typical evidence.

Our ability to navigate the business world depends on our ability to make cogent, logical arguments — of which the absence of evidence fallacy is one.  Understanding the arguments for God’s existence is a great way to cultivate our ability to present sound, rational arguments.  And a great way to strengthen our relationship with our Creator.