Causality

The philosophical concept of causality or causation refers to the set of all particular "causal" or "cause-and-effect" relations. A neutral definition is notoriously hard to provide since every aspect of causation has received substantial debate. Most generally, causation is a relationship that holds between events, objects, variables, or states of affairs. It is usually presumed that the cause chronologically precedes the effect. Finally, the existence of a causal relationship generally suggests that - all other things being equal - if the cause occurs the effect will as well (or at least the probability of the effect occurring will increase).

Nihilists subscribe to a deterministic world-view in which the universe is nothing but a chain of meaningless events following one after another according to the law of cause and effect. According to this worldview there is no such thing as "free will", and therefore, no such thing as morality. Learning to bear the burden of a meaningless universe, and justify one's own existence, is the first step toward becoming the "Übermensch" (English: "overman") that Nietzsche speaks of extensively in his philosophical writings.

Existentialists have suggested that people have the courage to accept that while no meaning has been designed in the universe, we each can provide a meaning for ourselves.

In light of the difficulty philosophers have pointed out in establishing the validity of causal relations, it might seem that the clearest plausible example of causation we have left is our own ability to be the cause of events. If this is so, then our concept of causation would not prevent seeing ourselves as moral agents.

http://en.wikipedia.org/wiki/Causality