We often use words like reality, belief, and truth without thinking much of what we mean by them. With some inspiration by J.P. Moreland I have devised a brief definition of each that makes it clear how they differ from each other.
Reality is the way the world really is independent of our beliefs about it.
Beliefs are what we think reality is like.
Truth is the corresponding relation between our beliefs and reality. If our beliefs about reality correspond to the way the world really is, truth is obtained. As J.P. Moreland says, truth puts us into contact with reality. We have truth when we have true, justified beliefs about reality.
We often confuse “truth” and “reality,” using the former to refer to the latter. I’ve noticed that even philosophers do this. While I think it is acceptable to use “truth” to refer to the way the world really is, it can cause confusion. Reality refers to what exists (ontology), while truth refers to our knowledge of what exists (epistemology). Technically speaking, truth does not obtain until a rational knower believes something about reality, and that belief just so happens to correspond to the way the world really is. Reality is what is apart from the knower, but truth is obtained only in the presence of a knower.
Let me make one final comment. I was listening to a lecture by Os Guiness a while back and he remarked that “beliefs do not command respect.” That is quite antithetical to our “tolerant” culture that teaches us to respect all beliefs. But Guiness’ remark is dead on. Beliefs are either true or false depending on how well they match reality. There is no reason to respect a belief about reality that does not correspond to reality. The only thing that commands respect is reality. That’s why we must evaluate every knowledge-claim to determine whether it corresponds to reality or not. If it does, then we respect that belief as being true. If it does not, then we do not respect the belief, although we still maintain our respect for the person who believes it while we try to persuade him otherwise.