Explain why it might be hard to determine the exact cause of an event

We cannot observe cause-effects relation directly. We infer these. In many cases, cause-effect is just an overall net effect of the actual process. For example, if you leave a glass of water on a table, the water will slowly dry out while water molecules enters the air. At the same time, air molecules will enter the liquid. The major direction is the water drying out. Another example, if you are a diabetic and imbibes soft drink with sugar you are under the risk of entering hyperglycemia, which then will make you crave for more sugar. What is then the cause and the effect? Often, there is a lot of noise in the measurements due to fluctuations in the process as well as insufficiently accurate and sensitive instrumentation. For example, mankind has tried to observe gravitational waves for few decades, but it is only recently that researchers succeeded to build an instrument that was able to detect perturbations in the space-time fabric of the universe. We need to simplify to analyze by abstraction (removing details) and we may loose information that can be vital in a different context. Correlation does not imply causation.

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