The question is also, in part, a recognition of how our senses work. Our bodies send information to the brain, which interprets it. It can also interpolate data as needed, such as the way it compensates for our visual blind spot. We actually need to fool the brain in order to 'see' the blind spot, because otherwise it just fills that void with data and we don't notice the effect.
We know the brain can present false data, such as pain signals (or lack thereof). If our perception of the world can be falsified by the very tool that allows us to percieve it... who knows what is possible? The behavior that leads to works like The Matrix is common enough that such ideas have been around for a very long time. There's one potential value to it: if I ever wake up in a vat of goo with a robot retracting some wires from my brain, I might actually know what is going on.