Telos (/'t?.l?s/; Greek: , translit. télos, lit. "end, 'purpose', or 'goal") is a term used by philosopher Aristotle to refer to the full potential or inherent purpose or objective of a person or thing, similar to the notion of an 'end goal' or 'raison d'être'. Moreover, it can be understood as the "supreme end of man's endeavour."
Telos is the root of the modern term teleology, the study of purposiveness or of objects with a view to their aims, purposes, or intentions. Teleology is central in Aristotle's work on biology and in his theory of the four causes. Aristotle's notion that everything has a telos also gave rise to epistemology. It is also central to some philosophical theories of history, such as those of Georg Wilhelm Friedrich Hegel and Karl Marx.
Telos has been consistently used in the writings of Aristotle, in which the term, on several occasions, denotes 'goal'. It is considered synonymous to teleute ('end'), particularly in Aristotle's discourse about the plot-structure in Poetics. The philosopher went as far as to say that telos can encompass all forms of human activity. One can say, for instance, that the telos of warfare is victory, or the telos of business is the creation of wealth. Within this conceptualization, there are telos that are subordinate to other telos, as all activities have their own, respective goals.
For Aristotle, these subordinate telos can become the means to achieve more fundamental telos. Through this concept, for instance, the philosopher underscored the importance of politics and that all other fields are subservient to it. He explained that the telos of the blacksmith is the production of a sword, while that of the swordsman's, which uses the weapon as a tool, is to kill or incapacitate an enemy. On the other hand, the telos of these occupations are merely part of the purpose of a ruler, who must oversee the direction and well-being of a state.
In contrast, techne is the rational method involved in producing an object or accomplishing a goal or objective; however, the two methods are not mutually exclusive in principle. These are demonstrated in the cases of writing and seeing, as explained by Martin Heidegger: the former is considered a form of techne, as the end product lies beyond (para) the activity of producing; whereas, in seeing, there is no remainder outside of or beyond the activity itself at the moment it is accomplished. Aristotle, for his part, simply designated telos as the consummation or the final cause of techne.
One running debate in modern philosophy of biology is to what extent does teleological language (i.e., the 'purposes' of various organs or life-processes) remain unavoidable, and when does it simply become a shorthand for ideas that can ultimately be spelled out non-teleologically.
According to Aristotle, the telos of a plant or animal is also "what it was made for"--which can be observed. Trees, for example, seem to be made to grow, produce fruit/nuts/flowers, provide shade, and reproduce. Thus, these are all elements of trees' telos. Moreover, trees only possess such elements if it is healthy and thriving--"only if it lives long enough and under the right conditions to fulfill its potential."
Action theory also makes essential use of teleological vocabulary. From Donald Davidson's perspective, an action is just something an agent does with an intention--i.e., looking forward to some end to be achieved by the action.Action is considered just a step that is necessary to fulfill human telos, as it leads to habits.
According to the Marxist perspective, historical change is dictated by socio-economic structures, which means that laws largely determine the realization of the telos of the class struggle. Thus, as per the work of Hegel and Marx, historical trends, too, have telos.