A couple of days ago I became embroiled in a long-running Twitter debate about the nature of truth and knowledge, during which at least one person fell asleep. @EdSacredProfane has asked me where I ‘sit’ on truth. So, for the record, here’s what I think about truth and knowledge.
1. I think it’s safe to assume that reality and truth are out there. Even if they’re not out there and we’re all experiencing a collective hallucination we might as well assume that reality is real and that truth is true because if we don’t, our experience – whether real or imagined – is likely to get pretty unpleasant.
2. I’m comfortable with the definition of knowledge as justified true belief. But that’s a definition of an abstract concept. The extent to which people can actually justify or demonstrate the truth of their beliefs (collectively or individually) varies considerably.
3. The reason for this is the way perception works. All incoming sensory information is interpreted by our brains, and brains aren’t entirely reliable when it comes to interpreting sensory information. So we’ve devised methods of cross-checking what our senses tell us to make sure we haven’t got it disastrously wrong. One approach is known as the scientific method.
4. Science works on the basis of probability. We can never say for sure that A or B exists or that C definitely causes D. But for the purposes of getting on with our lives if there’s enough evidence suggesting that A or B exists and that C causes D, we assume those things to be true and justified to varying extents.
5. Even though our perception is a bit flaky and we can’t be 100% sure of anything, it doesn’t follow that reality is flaky or not 100% real. Just that our knowledge about it isn’t 100% reliable. The more evidence we’ve gathered, the more consistent and predictable reality looks. Unfortunately it’s also complicated, which, coupled with our flaky and uncertain perceptions, makes life challenging.