At the beginning of its history, philosophy separates tekhné from épistémé, a distinction that had not yet been made in Homeric times. The separation is determined by a political context, one in which the philosopher accuses the Sophist of instrumentalizing the logos as rhetoric and logography, that is, as both instrument of power and renunciation of knowledge. (ref to Francois Châtelet, Platon, in Bernard Stiegler, Technics and Time, p.1) (is this a reference to Plato's Phaedrus?) 

In Heideggerian vocabulary, the techné of the Western project is an instrumentality that takes over, arrests, or enframes what it desires to manipulate or contain. This is the Gestell, the systematization of the principle of reason in the technical process of ratio , the ar-raisonnement of knowledge. To this "enframed" use of technology Heidegger opposes an ostensibly older techné that the Greeks called poesis, a bringing-forth, a setting-on-the-path toward revelation, truthbeing, or essence. As production (poesis), technics is a way of revealing. As he put in in the celebrated sentence in "The Question Concerning Technology", "The essence of technology is nothing technological." 

Techné is usually translated as art, but it means more precisely the orderly application of knowledge for the purpose of producing a specific, predermined product. In the Nicomachean Ethics, Aristotle writes: "Every art (tekhné) is concerned with bringing something into being, and looks for technical and theoretical means of producing a thing which belongs to the category of possibility and the cause of which lies in the producer and not in what is produced." For Aristotle, techné sets itself up between nature and humanity as a creative mediation to create what nature finds it impossible to achieve. (Félix Guattari, "Machinic Heterogenesis", in Rethinking Technologies) According to Guattari, Heidegger sets techné on an ontological pedestal -- a Grund -- that compromises its definition as a process of opening. (see ground / foundation ) 

Max Weber saw instrumental rationnality as part of the modernizing process, as the "value free" calculable efficiency of administrative process. Rationalization represents the phenomenon of an irresistible extension of those domains of society subject to the criteria of rational decision and the correlative industrialization of work. It characterizes capitalism. Marcuse added to this the idea that rationalization is in fact a hidden system of domination (which, for some feminists, is a gendered behaviour, part of the masculinist project of domination, arising out of the denial of dependence and its substitution by possession and control) Instrumental rationality is a "normalizing" and " disciplinary" rationality. 

Adorno, Horkheimer, and Marcuse collapsed the two processes of rationalization, the societal and the cultural, that Weber had sought to differentiate. In the wake of the analysis of Fascism and the Frankfurt School's description of the transformation of private capitalism into state capitalism, the research programme of the Institute for Social Research from 1940 to 1945 has been described as "the critique of instrumental reason." "Rationalization" and "instrumental reason" were used to describe t he organization principles of social formation, the value orientations of the personality, and the meaning structures of the culture. For the Frankfurt School, technology is a form of "instrumental reason," of the "reification of reason, reification as reason," that suspends all judgement on its inner logic. (see Marcuse Negations) Habermas's critique of instrumental rationality is that systems rationality, and economic and bureaucratic rationality in particular, threatens the communicative processes that sustain the life-world. The encroachment of the system into the lifeworld renders patterns of meaning functional. They serve to legitimate the imperatives of the system and replace moral-practical considerations with technical ones. Thus the Nazi Holocaust epitomizes the rational, efficient processing of people as things. (Although Jameson describes Habermas as subscribing to a notion of enlightenment which Adorno and Horkheimer identified with the final solution.) (see modernism ) 

For some authors, a praxis is the locus of meaning that avoids the nihilism associated with both instrumentality and techné . It is a concept of a integration of theory and practice. This is the way in which American pragmatists such as John Dewey describe intrumentality, in Richard Rorty's characterization "an arsenal of tools people use for gratifying, sythesizing, and harmonizing their desires." 

J.J. Gibson (in The Ecological Approach to Visual Perception) introduced the concept of "affordance" to describe the dispositions and powers of physical systems in response to human requirements. Thus a sharp knife "affords" cutting. 

Analytic philosophers debate whether science is an account of reality (realism) or a useful tool for coping with it (instrumentalism). Philosophers of technology can also be "instrumental realists", by considering scientific theories as realist, but mediated through the use of instruments. (see tool and "instrumental transparency") 

The instruments of science, from the telescope and microscope to computer graphics, extend the realm of perceptability and constitute new perceptual objects. The instruments of science are considered to be "Transparent" instruments that afford accurate representations of states of nature because we believe that, in the case of this class of instrument, determinate states of the physical world interact with the instrument to yield determinate and observable states of whatever physical system constitutes the instrument itself. Instruments used to detect or measure quantum phenomena, however, are not transparent. A quantum mechanical "state of the world" consists of an ensemble of wave states any one of which, with differing likelihoods, could be realized when the world and the instrument interact. (see Rom Harré, Laws of Nature, p.47) Niels Bohr's interpretation of this situation was to treat the laws of quantum mechanics not as descriptions of the world as it exists independently of the instruments used to study it, but as descriptions of the affordances of indissoluble instrument / world complexes. 

Michael Polanyi, stressing the indeterminate dimensions of all scientific thought, points out that "any correlation between a measured number introduced into an exact theory and the corresponding instrument readings, rests on an estimate of observational errors which cannot be definitively prescribed by rule."" (Personal Knowledge, p. 19) 

Productive imaging picks up where instrumental realism ends.

In a spirit of play, we might prefer to talk of the instrumental the way the term is used to describe a piece of music. The instrumental version of a song, for instance, is a song without words. Learning to play an instrument requires the development of tacit knowleges.