Some Concepts

Translation

Central to ANT (some times referred to as Sociology of Translation) is the concept of translation, in which innovators attempt to create aforum, a central network in which all the actors agree that the network is worth building and defending. In his widely debated 1986 study of how marine biologists try to restock the St Brieuc Bay in order to produce more scallops,[4] Michel Callon has defined 4 moments of translation. These four moments are derived from studying:

1. Problematisation

What is the problem that needs to be solved? Who are the relevant actors? Delegates need to be identified that will represent groups of actors. So, a union head represents workers or a Member of Parliament represents his constituency. During problematisation, the primary actor tries to establish itself as an obligatory passage point (OPP) between the other actors and the network, so that it becomes indispensable.

2. Interessement

Getting the actors interested and negotiating the terms of their involvement. The primary actor works to convince the other actors that the roles it has defined them are acceptable.

3. Enrolment

Actors accept the roles that have been defined for them during interessement

4. Mobilization of allies

Do the delegate actors in the network adequately represent the masses? If so, enrollment becomes active support.

Intermediaries and Mediators

The distinction between intermediaries and mediators is key to ANT sociology. Intermediaries are entities which make no difference (to some interesting state of affairs which we are studying) and so can be ignored. They transport the force of some other entity more or less without transformation and so are fairly uninteresting. Mediators are entities which multiply difference and so should be the object of study. Their outputs cannot be predicted by their inputs. From an ANT point of view sociology has tended to treat too much of the world as intermediaries.
For instance, a sociologist might take silk and nylon as intermediaries, holding that the former ‘means’, ‘reflects’, or ‘symbolises’ the upper classes and the latter the lower classes. In such a view the real world silk-nylon difference is irrelevant - presumably many other material differences could also, and do also, transport this class distinction. But taken as mediators these fabrics would have to be engaged with by the analyst in their specificity: the internal real-world complexities of silk and nylon suddenly appear relevant, and are seen as actively constructing the ideological class distinction which they once merely reflected.
For the committed ANT analyst, social things - like class distinctions in taste in the silk and nylon example, but also groups, power etc - must constantly be constructed or performed anew through complex engagements with complex mediators. There is no stand-alone social repertoire lying in the background to be reflected off, expressed through, or substantiated in, interactions (as in an intermediary conception).

Generalized Symmetry

ANT assumes that all the elements in a network, human and non-human, can and should be described in the same terms. This is called the principle of generalized symmetry. The rationale for this is that differences between them are generated in the network of relations, and should not be presupposed.

Actants

ANT defines, for instance, Actants to denote human and non-human actors, and assumes that actants in a network take the shape that they do by virtue of their relations with one another. It assumes that nothing lies outside the network of relations, and as noted above, suggests that there is no difference in the ability of technology, humans, animals, or other non-humans to act (and that there are only enacted alliances.) As soon as an actor engages with an actor-network it too is caught up in the web of relations, and becomes part of the 'entelechy'.

Punctualisation
If taken to its logical conclusion, nearly any actor can be considered merely a sum of other, smaller actors. An automobile is an example of a complex system. It contains many electronic and mechanical components, all of which are essentially hidden from view to the driver, who simply deals with the car as a single object. This effect is known as punctualisation, and is similar to the idea of abstraction in object-oriented programming.
When an actor network breaks down, the punctualisation effect tends to cease as well. In the automobile example above, a non-working engine would cause the driver to become aware of the car as a collection of parts rather than just a vehicle capable of transporting him or her from place to place. This can also occur when elements of a network act contrarily to the network as a whole. In his book 'Pandora's Hope', Latour likens depunctualization to the opening of Pandora's box.

Tokens/quasi-objects
In the above examples, 'social order' and 'functioning car' come into being through the successful interactions of their respective actor-networks, and actor-network theory refers to these creations as tokens or quasi-objects which are passed between actors within the network.
As the token is increasingly transmitted or passed through the network, it becomes increasingly punctualized and also increasingly reified. When the token is decreasingly transmitted, or when an actor fails to transmit the token (e.g., the oil pump breaks), punctualization and reification are decreased as well.