In my work and my world, I am dealing routinely with whiplash-inducing headlines about health, and nutrition in particular (“no, wait, fruits and vegetables are bad for us this week!”) that raise questions about science, sense, and knowledge. When whatever we think we know, however reliably we think we know it, is called into question so routinely, it begs the question: how do we know?
My question is not how do we know any given thing, but rather – how do we know anything, ever, at all? The surprising answer is, we do not. Not unless we decide to trust our nervous systems and the perceptions they engender, for which there is a compelling case.
We do not, truly, know anything because all we can do is perceive. Were we in a virtual reality, like the one portrayed in the science fiction classic, The Matrix, we would likely be unable to know it, or prove it. We cannot disprove it now, either, since all of our perceptions of all of our disproofs would take place in the same virtual reality, reinforce it, and do nothing to tell us it wasn’t real.
We really can’t know anything for sure. But we can choose to have faith in the veracity of our impressions here, and build knowledge from them. If our perceptions are reliable, then what we derive from them is reliable, and so, too, are the embellishments of science, which are, essentially, extensions of our native perceptions via instruments and assays, lenses and equations.
It makes sense that our nervous systems and perceptions would be reliable since they are the ones we have here, wherever here is, and thus they are the ones adapted to be here. They are the perceptions that help us survive in this place where we are surviving.
We can, in effect, choose to have faith in our perceptions, and build our understanding from that foundation. The only alternative is to renounce the reliability of the only reality we know, and never understand anything. Most of us have made the choice…