Jonny Thomson on Instagram: "A long time ago, I read a thought experiment from the British philosopher John Locke, and it was what inspired me to go on to study philosophy. It’s a question and a thought that I suspect many people have as well. It goes like this: imagine that there are two perfectly healthy people with perfectly functioning sense organs, and they are on a walk, and one turns to the other and says, ‘Wow, look at that beautiful blue sky!’ And the other one nods along and agrees. No