Causation

Definitely fake. Useful though, so I would agree with Aaron that it's conventionally real. I think it's helpful to think of causation-talk as metaphorical. IIRC Garfield uses an example that goes something like this: We can make true claims about X being the cause of Y even if there are no actual *causes* out there in the world, just as we can say "He did X for the sake of Y" even though there are no "sakes" and "She ran out of luck" even though "luck" isn't an actually existing entity. You can think of lots of other examples.