Causes and effects are discovered, not by reason but through experience, when we find that particular objects are constantly conjoined with one another. We tend to overlook this because most ordinary causal judgments are so familiar; we've made them so many times that our judgment seems immediate.
So what happens when experience, as in carefully controlled experiment, demonstrates an absence of causation?
Sorry, missed this question earlier. The question is a good one, but is poorly worded. The reason is that causation is not an empirical entity and we can observe neither its presence nor its absence (again, thanks Dave). We do not "observe" (my word, not yours) causation at all, but rather infer it from experience. The question then becomes what about when we run carefully controlled experiments and the behavior of the observed entities do NOT give us reason to infer causality? This does not "demonstrate an absence of causality" but simply states that the behavior of what we observe here does not give us reason to infer it. Our options then seem to me to be two:
1) Assume that causality itself fails on the level we are observing, or
2) Assume that there are properties in what is being observed that we do not fully understand and assume that when they are more fully comprehended, the principles of causality will be seen to be applicable.
I guess you can tell where I am at present. At any rate, thanks for interacting,and please be assured that I am always open to shifting my perspective, should I be convinced that I need to do so.