About 6 months ago, I wrote a post called “Arguments and Evidence – Should an Argument Be Considered Evidence?” where I examined the relationship between arguments and evidence. The conclusion of my analysis was this:
Evidence is used in justification for certain truth-bearing propositions. An argument is a series of truth-bearing propositions, logically leading to a conclusion. If the premises of an argument are justified by evidence, and the argument is both valid and sound, the conclusion logically follows.
That logical conclusion from the evidence is also evidence for a certain conclusion. So, an argument is evidence. However, this is not meant to be a bifurcation between the concepts. Arguments and evidence are interdependent upon each other.
I think my point is rather trivially true, but not everyone seems to agree with me.
I think its because they don’t actually understand my point. I did my best to respond in the comments section of the previous post, but I received a blog response from @nonprophetess titled “An Argument for Evidence“. This post highlights the primary misunderstanding behind the rejection of my conclusion.
She didn’t particularly like the evidence for my mortality, in the form of this argument:
1. All men are mortal.
2. Elijiah is a man.
3. Therefore, Elijiah is mortal.
We had a several discussions on twitter (some were good, others were rather silly) where I offered some responses to some of her critiques, but ultimately… I realized I needed to write something more extensive in response.
To repeat my conclusion, but in a way that responds directly to @nonprophetess, allow me to say it this way:
Evidence can be defined as the available body of facts or information which tends to prove or disprove something, usually associated with the justification for beliefs.
An argument can be defined as a collection of truth-bearing statements, reasons or facts used in support of an idea, theory or belief. Arguments are used to rationally persuade its audience of a particular conclusion.
A valid argument is an argument that does not commit any logical mistakes.
A sound argument is a valid argument that has true premises.
When we have a valid and sound argument, we have facts or information which tends to prove or disprove something, usually associated with the justification for beliefs.
If a valid and sound argument is used to prove or disprove something, then a valid and sound argument is evidence for or against something.
Interestingly enough, I’ve noticed that many atheists have constructed arguments against God’s existence, and rightfully conclude that these arguments (assuming that they are, in fact, valid and sound) would be evidence against the existence of God.
I disagree with them, of course, but that’s another post entirely.
NonProphetess’ (and many other people’s) disagreement comes from an apparent misunderstanding of how soundness works. Its important to realize that I have never claimed that a mere argument is evidence, despite their constant claims to the contrary.
In order for an argument to be evidence for anything, the argument must be both valid and sound.
If it is invalid, it is not evidence.
If it is unsound, it is not evidence.
When you offer justifications for a particular premise in an argument, you are defending the soundness of the argument itself. If it turns out that we have no reason to believe premise 1 in an argument, the argument is no longer evidence for its conclusion.
And this is where nearly all of the discussions concerning evidence for God’s existence go, and rightfully so. As long as you’re not making a logical mistake, discussions focus on the reasons to believe the premises.
As I said earlier, I don’t think my point here is controversial, as long as we have a proper understanding of evidence and argument. And because of this, I believe the response to @nonprophetess’ objection is actually within the original post itself, but it just needed a little more clarification.
Hopefully I’ve succeeded in providing that clarification.
However, this gives me the opportunity to elaborate on the point a bit, and make an even stronger point. Not only is an argument evidence, but an argument is often times required when discussing the reasons to believe a certain thing.
If your friend says, “i have a red 2014 Maserati”, it is not unreasonable to ask for evidence. If she shows you her beautiful car, then you have evidence for her claim.
As I was discussing with a recent commenter on this post, not everything is this simple.
A lot of times, a logical inference is essential for proper reasoning.
Take common descent for example.
One of the many evidences presented for common descent is homology. We have direct experience (empirical evidence) with structures that are similar. However, if we just look at the direct observation or experience, we don’t actually have evidence for common descent. And this is because similar structures are evidence for similar structures. That’s it.
In order to say that it is evidence for common descent, there must be a logical flow of thought; something that connects the ‘direct observation’ to common descent.
Another example would be the age of the earth (yes, I am an ‘old earther’)
We have quite a bit of good evidence for the age of earth. I would imagine many of you would agree. However, this evidence is almost exclusively in the form of a valid and sound argument.
Think about it. We have rocks/meteorites and radioisotope data, right? But exactly how do we get from looking at the rocks to the 4.5 billion year old earth? Well, we gotta take what we know about the decay rates of radioisotopes, factor in potential variables, calculate the half-life of a particular isotope, etc. Much like my common descent example, we must rely on valid inferences; there must be a logical flow of thought that connects the ‘direct observation’ to the age of the earth.
For both evolution and the age of the earth, we rely on valid and sound arguments as evidence to support a particular propositions. We may not always explicitly state our arguments for these things in modus ponens, but there is an argument there. Without it, we wouldn’t actually have evidence for evolution or the age of the earth.
Much of what we have evidence for/against is a combination of empirical evidence and logical inference towards/away from conclusion.
To conclude, here is my recommendation.
Don’t just assert that you need direct, physical evidence for something. Examine the reasons for believing something, and do your best to consider the evidence presented. Often times, expecting a specific type of evidence will force you into being inconsistent in examining evidence for different things.
Thanks for reading!
I did also get a response from @BuyBullJournal on my article. You can find that here.
His primary misunderstanding is that my article was merely an epistemological analysis of evidence. I never suggested that it would present evidence for Christianity.
I think his entire post can be summed up using a quote from him. After citing Oxford Dictionary’s definition of evidence, his response is:
“WTF?! Alright, either Elijiah is insane, or somehow thinks he’s making a point, or I am insane! How is what he says here even a point at all? This is crazy! I’m sorry, but I can’t be nice about this.”
He then proceeds to show his disdain for philosophy, call me a liar, says that I use the bible to prove the bible, and other stuff.
Interestingly, he says this at the end:
“Yes an argument CAN be a form of evidence, but only if there is some sort of truth, or facts that are true to back it up”, so apparently he and I agree on the point that I was actually making.
So… feel free to read that one too.