Teleology
final cause · teleological explanation
Explanation by reference to ends or purposes — saying what something is for, rather than only what caused it.
In practice
Saying a process exists to catch errors is teleological. It is true if the process was adopted for that reason, and false if it accumulated and was rationalized afterwards — and the two look identical from inside.
The common mistake
Assuming teleology requires a designer. Aristotle applied it to organisms with no intending mind involved, and natural selection explains the appearance of purpose without one.
Teleology explains by pointing forward. A heart is explained by what it does; an acorn's development is explained by the oak it is becoming. The explanation cites an end rather than only a prior cause.
Aristotle's version
Aristotle made final cause one of the four causes, and treated it as the most important for understanding living things. Nature, on his account, does nothing in vain: organisms have parts that exist for functions, and describing the function is part of saying what the part is. See telos.
The purpose need not be anyone's intention. The acorn is not trying to become an oak; becoming an oak is what its development is directed at, which is a claim about the process rather than about a mind behind it.
Why early modern science dropped it
The new physics explained by prior causes and mathematical law, and final causes did no work there. Bacon complained that teleology was sterile — like a virgin consecrated to God, it produced nothing. Explanation narrowed to efficient causation, and "formal cause" and "final cause" came to sound archaic.
Biology could not follow. Hearts obviously seem to be for pumping blood, and no reformulation in purely mechanical terms captured what a physiologist meant.
Darwin's resolution
Darwin supplied what was missing: a mechanism that produces the appearance of purpose without any purposing. A heart is for pumping blood because pumping blood is why hearts were selected — a claim about history rather than about a goal.
This licenses functional language in biology without metaphysical commitment, and it is why biologists talk about what a trait is for while physicists do not.
Where it remains contested
In ethics, whether human beings have a natural end that grounds what is good for them — the assumption underneath virtue ethics and natural law, and the one MacIntyre argues modern moral philosophy discarded while keeping the vocabulary that depended on it.
And in history and politics, whether events tend toward an end — the historicism Popper attacked.
Concept web
Open the full webQuestions
What is teleology?
Explanation by reference to ends or purposes — saying what something is for rather than only what caused it. Aristotle made it one of his four causes.
Why did science abandon teleology?
Because the new physics explained by prior causes and mathematical law, where final causes did no work. Biology could not follow, since organs plainly seem to have functions.
How did Darwin rescue functional language?
By supplying a mechanism producing apparent purpose without any purposing. A heart is for pumping blood because that is why hearts were selected, which is a claim about history rather than a goal.