On my desk is a tube of lip balm. If I hold it between my fingers, ready to drop it, how do I know it will fall?
It seems like a very simple question, but I don’t think it is. I can dumb it down much, much further.
The most fundamental level of knowledge is the present sensory experience. I know THIS more than anything else.
We don’t need to know how we sense reality, only that we sense reality.
We have a memory, which, on its own, is not enough to consider knowledge. But then what validates our memories?
Our capacity for reason: our intelligence.
The simplest question I suppose you could ask, without worrying about the self-evident sensory experience, is how we know there will be a future.
How do we know there will be a future?
First comes the conception of time: Our memory records and retrieves sensory information in order of occurrence.
We validate our memory of half a second ago by acknowledging it’s consistency with our present sensory experience. We see that reality is here, and remember that it was here, and so we conclude that in half a second from now it will still be here.
Can we continue this process of reasoning to eventually explain how we can know something like gravity?
Well… yes, I think we can. Gravity is a constant in all the moments of experience. There are certain parameters that through their constant recurring are predictable to the subconscious mind, like different laws of physics. When you were a kid, weren’t you more ready to believe that the lip balm might float away than you are now? Wasn’t playing pretend given power by the fact that, who knows, that shit could happen?
But now, the parameters have been recurrent for so long that it is harder to imagine them changing. Still, some people still believe that Jesus walked on water. It’s because we realize that the fact that these parameters have been given facts this far doesn’t imply that they are absolute, “immortal”.
Some of us don’t believe the wlaking-on-water thing because those that practice the discipline of science have found ways to play with these recurring parameters in ways that allow for even greater certainty that they will remain the same.