Correlation or Causation?
We search for certainty all the time. It’s a human dilemma. When babies who are not following the path of ‘average’ development or become unwell, we look for certainties even more.
When a health professional diagnoses a disease, they inevitably are involved in questions of cause and effect with the patient in the sessions leading up to the diagnosis. A doctor can’t treat effectively without understanding possible causes, whether they are environmental (outside the body affecting it) or physiological (affecting the body from within).
Most parents with a baby, confronted with an illness, ask the question, “Why?” Or, even more painfully, “Why me?” Despite these questions, they may already have arrived at their own theory of causes, very often involving a sequence of events, that may or may not follow. There’s a fancy name for this in Latin: post hoc ergo propter hoc— After this, therefore because of this.”
It’s irresistible to make an association between two events that occur together, and often these associations are right—but sometimes they’re wrong. Distinguishing correlation from cause depends on the quality of the evidence and the strength of the association.
The search for cause can be a serious pursuit which can also falsely elevate hope. Establishing a definitive cause can be difficult because circular events don’t have a clear point of origin. The very notion of homeostasis—A causes B affects A—depends on feedback loops, making it difficult to identify a “prime mover.”
Source: Excerpts from Julian L. Seifter, MD ‘Correlation or Causation? Our Search for Certainty’