Knowledge and truth are not the same thing, and science, as much as we might hate to admit it, does not tell us what is the truth, it can only provide us with a framework to gain knowledge. And while knowledge continually strives after truth, it can never fully reach it in its entirely, because we aren't omniscient. We can never know everything there is to know about everything, even though our knowledge continues to grow over time.
Science is more about understanding the natural world in a way that is useful to us. For example, weather prediction. Over the past several hundred years, our methods of weather prediction have grown increasingly more sophisticated, and we now have tools like radar and satellite imaging at our disposal, where once all we had was looking up at the sky. Our knowledge of how weather generally works in a local and global scale has increased through many years of observation, and we now have fairly reliable patterns, which helps us to generally predict weather with accuracy that is useful. But as we're all aware by how frequently we berate our local weathermen for not forecasting something correctly, science cannot tell us the truth about what the weather WILL certainly be, it can only give us models that get more and more useful over time as more and more knowledge and tools are available to us.
Take gravity, which could be considered a "truth" in the sense that is a law of physics that undeniably exists, yet we had startlingly little knowledge about how gravity works on a cosmic scale until recently, because we didn't have enough knowledge to construct a useful model that both represented what we see from gravity and predicted results with accuracy. But we all know gravity is "true", even though science was without functional mathematical knowledge of it.
Even our conversation about taxonomy on another thread recently falls in line with this. The taxonomic system of binomial nomenclature exists only as a convenient way to organize the natural world, and as our knowledge of individual species increases, it's continually edited to make sure it remains useful. But in no way does taxonomy attempt to say that Apis mellifera is the true name of the honey bee and all other names are false. It's simply the way we are currently classifying the honey bee, to the best of our modern knowledge.
