The extent to which our presuppositions shape how we interpret data can hardly be overstated.
To consider one excellent example, let’s take a look at how an atheist and a Christian would differ in how they assess the significance of the size of the universe.
First up, let’s consider atheism. The following popular youtube video goes through a catalogue of increasingly large celestial objects. That’s all fine. But then it closes in on the conclusion that you are not the center of the universe. The video can be taken to be an example of the Copernican Principle according to which the earth does not occupy a privileged or special place in the cosmos. By implication, human beings do not occupy any special place in the cosmos. Granted this doesn’t get you to atheism — for example, there could be a creator God who doesn’t care about us — but it does get us close. (For more discussion of this video see my article “You’re not special because the universe is really, really big.”) Anyway without further ado:
And then there are Christians looking at the same data and drawing very different conclusions. Suddenly when you get to church the very same data has a very different meaning. Rather than saying “You’re not special” it now says “God is awesome”. Consider this popular pastor, Louie Giglio:
At this point we might be tempted to ask “So who is right? Is the atheist right to think the universe says we’re not special? Or is the Christian right to think it shows that God is great?” The answer is both and neither. In other words, if you begin with atheistic assumptions then you will predictably (but not necessarily) draw the conclusion that the size of the universe supports atheism. If you start with Christian assumptions then you will predictably (but not necessarily) draw the conclusion that the size of the universe supports Christian theism.
So both.
And as I said, also neither. Given that different presuppositions can interpret the data differently we have good reason to believe that the data itself underdetermines its own interpretation. Simply learning that the universe is vastly large and that there are huge objects within it doesn’t provide any evidence in and of itself either for atheism or (Christian) theism. The evidence, such as it is, awaits interpretation relative to a set of presuppositions.
There are many lessons one might draw from this fact. Let’s close with two of them.
First, do not adopt a triumphalistic attitude regarding your own worldview because much of the evidence you appeal to in support of your worldview is already interpreted to support the assumptions you hold.
Second, extend some charity to those with other worldviews because they’re probably interpreting the same data from a very different starting point. And as a result (to allude to one of my books), they’re probably not as crazy as you think.
For further reading see my article “Does a really old universe show that human beings are not important?”