Saturday, September 10, 2016
One of the problems with human language is that it sometimes doesn't capture the true nature of reality, and one word where this is the case is the word cause. Fundamentally speaking, there are no causes in the way we traditionally speak of them. There are simply just worldtubes or particles in spacetime and one point on the worldtube doesn't really "cause" a later point on the worldtube to exist. What causality really is would seem to have to be the relationships of intersecting worldtubes as they precede or intertwine with one another in spacetime; they're a description of the relationship between patterns and boundary conditions. At the fundamental level, the word "cause" really should be replaced by the word "explanation" or "relationship."
For example, asking "why do I exist now?" would be explained by the fact that at an earlier event in spacetime my parents had sex. That was the "cause" that resulted in my birth and existence now – but only in the sense that if you trace my worldtube back in spacetime to its origin it’s preceded by my parent’s worldtubes and thus that establishes the "causal" relationship. But even the terms "earlier" and "preceded" here are a bit misleading because they imply that there's an intrinsic directionality of time. However, no good data backs that up. Instead, the data strongly suggests the directionality of time is dependent on the increase in entropy. These are profound insights that radically changes our notion of causality.
So when it comes to our language, what should we do? Well, I'm not saying we jettison the word "cause" anymore than we jettison the word "solid," even though solidity is not found in the fundamental nature of reality either. It's an emergent phenomenon that exists at higher (non-fundamental) levels. Causality exists in much the same way: "cause" is a useful word to describe an emergent phenomenon that makes sense when talking about our human-level experience, but we shouldn't confuse language with reality. Human language is far better at capturing human experience than at expressing deep physical laws. We need to be aware of what causality really is, apart from its everyday usage. This of course is much easier said than done.