Recently I was speaking to a group of pastors, youth pastors, and other church workers in Idaho. One pastor asked a question that, in my experience, perfectly captures the thinking process of many students today. He said, “My younger brother, a Millennial, is constantly on his cell phone. When I try to talk to him about God, he says that people disagree and so we simply can’t have any confidence at all in our beliefs.” How would you respond? Can we know things or are we lost in a sea of endless information?
Young people today are exposed to more information than any generation in history. Since they are constantly barraged with information, and encounter such a wide array of perspectives, many wonder if they can even know anything at all.
The question of how we know things is part of the discipline known as epistemology. It is a branch of philosophy that wrestles with questions such as: What is knowledge? What makes a belief justified? How do we know things? This young man embraced a version of skepticism, which questions whether we can know anything at all.
While there are many challenges that can be raised to skepticism, one important tactic is to begin by pointing out that we all do have some knowledge that we take for granted. In other words, the place to begin our investigation is the recognition that we really do have some instances of knowledge. And then we can come up with a criterion for how we know these cases in particular and extend that criterion to unclear, difficult cases.
In his classic book Love God With All Your Mind, J.P. Moreland explains how this works in practice:
"We start by knowing specific, clear items of knowledge: for example, that I had eggs for breakfast this morning; that there is a tree before me or, perhaps, that I seem to see a tree; that 7 + 5 = 12; that mercy is a virtue; and so on. I can know some things directly and simply without needing criteria for how I know them and without having to know how or even that I know them. We know many things without being able to prove that we do or without fully understanding them. We simply identify clear instances of knowing without have to possess or apply any criteria for knowledge. We may reflect on these instances and go on to develop criteria for knowledge consistent with them and use these criteria to make judgments in borderline cases of knowledge, but the criteria are justified by their congruence with specific instances of knowledge, and not the other way around." 
When people say to me, like the young man above, that there’s so much information and therefore we can’t know anything, I simply bring them back clear cases of things they do in fact know to be true (besides, if we didn’t at least know some things, we couldn’t doubt anything. After all, doubting that your senses are reliable now assumes they were reliable in the past).
For instance, can we know the earth is round? Yes. Can we know the Holocaust happened? Definitely. Is torturing an innocent child for fun wrong? Of course. In my experience, people willingly admit that we can know these things, even though there may be some people may challenge them. If we can at least know some things, which we all demonstrate to be the case by our practice, then there is no need for despair.
Does this mean gaining knowledge is always easy? Of course not. Discerning truth is often difficult and costly. And sometimes truth is beyond our grasp. The endless array of information and perspectives can be intellectually (and emotionally) overwhelming. It is easier to conclude that the endless information and competing perspectives available today undermines the possibility of knowledge.
But far too much is at stake. And it doesn’t follow logically from this that we can’t know anything at all. We all know some things. Even the skeptic who says we can’t know things seems to at least know that we can’t know things. It’s inescapable.
 J.P. Moreland, Love God With All Your Mind (Colorado Springs, CO: NavPress, 1997), 140.