1.3.2: The Function Argument

Aristotle was a teleologist, a term related to, but not to be confused with, the label “teleological” as applied to normative ethical theories such as Utilitarianism. Aristotle was a teleologist because he believed that every object has what he referred to as a final cause. The Greek term telos refers to what we might call a purpose, goal, end or true final function of an object. Indeed, those of you studying Aristotle in units related to the Philosophy of Religion may recognise the link between Aristotle’s general teleological worldview and his study of ethics.

Aristotle claims that “…for all things that have a function or activity, the good and the ‘well’ is thought to reside in the function”. Aristotle’s claim is essentially that in achieving its function, goal or end, an object achieves its own good. Every object has this type of a true function and so every object has a way of achieving goodness. The telos of a chair, for example, may be to provide a seat and a chair is a good chair when it supports the curvature of the human bottom without collapsing under the strain. Equally, says Aristotle, what makes good sculptors, artists and flautists is the successful and appropriate performance of their functions as sculptors, artists and flautists.

This teleological (function and purpose) based worldview is the necessary backdrop to understanding Aristotle’s ethical reasoning. For, just as a chair has a true function or end, so Aristotle believes human beings have a telos. Aristotle identifies what the good for a human being is in virtue of working out what the function of a human being is, as per his Function Argument.

Function Argument

1. All objects have a telos.
2. An object is good when it properly secures its telos.

   Given the above, hopefully these steps of the argument are clear so far. At this point, Aristotle directs his thinking towards human beings specifically.

3. The telos of a human being is to reason.
4. The good for a human being is, therefore, acting in accordance with reason.

In working out our true function, Aristotle looks to that feature that separates man from other living animals. According to Aristotle, what separates mankind from the rest of the world is our ability not only to reason but to act on reasons. Thus, just as the function of a chair can be derived from its uniquely differentiating characteristic, so the function of a human being is related to our uniquely differentiating characteristic and we achieve the good when we act in accordance with this true function or telos.

The notion that man has a true function may sound odd, particularly if you do not have a religious worldview of your own. However, to you especially Aristotle wrote that “…as eye, hand, foot and in general each of the parts evidently has a function, may one lay it down that man similarly has a function apart from all these?”

On the basis that we would ascribe a function to our constituent parts — we know what makes a good kidney for example — so too Aristotle thinks it far from unreasonable that we have a function as a whole. Indeed, this may be plausible if we consider other objects. The component parts of a car, for example, have individual functions but a car itself, as a whole, has its own function that determines whether or not it is a good car.