Where does mechanism collide?

In economics and game theory, a mechanism is a set of rules, such as an auction or a voting procedure, deliberately engineered so that self-interested people, each acting on private information, are led to an outcome the designer wants. The field is sometimes called reverse game theory: rather than analysing a fixed game, it builds the game backwards from the result it seeks. Myerson's 1981 Optimal Auction Design showed how a seller can set the rules of an auction to maximise expected revenue given that bidders know their own values and will bid strategically. This meaning is an abstract structure of incentives and rules, not a chemical pathway, a linkage of metal parts, or a system of parts in nature.[1]

Unit

One institution or game form: a rule set mapping the participants' reported information to an outcome

Recovery means

Not applicable

Measured by

Analysed formally by its equilibrium behaviour, checking whether the truthful or desired action is each player's best response

In chemistry, a reaction mechanism is the step-by-step sequence of elementary reactions by which starting materials are converted into products, including the short-lived intermediates and transition states that appear along the way. It specifies which bonds break and form at each step and in what order, so that the overall change is resolved into a detailed pathway rather than a single arrow. The IUPAC glossary compiled by Muller in 1994 defines the term as the full account of the elementary steps by which reactants become products. This meaning is a molecular pathway inferred from rates and structure, not a set of auction rules, an assembly of rigid links, or a philosopher's explanatory system.[2]

Unit

One reaction pathway: an ordered set of elementary steps with intermediates and transition states

Recovery means

Not applicable

Measured by

Inferred from reaction rates, kinetic isotope effects, detected intermediates, and stereochemical outcome

In mechanical engineering, a mechanism is an assembly of connected rigid bodies, called links, arranged so that they transmit force and motion in a determined way, as in a four-bar linkage where the movement of one link fixes the movement of the others. Reuleaux's 1876 The Kinematics of Machinery founded the modern theory, treating a machine as a kinematic chain of paired links whose relative motions are constrained by their joints. The referent is a physical arrangement of parts that converts an input motion into a wanted output motion. This meaning is a tangible linkage of hardware, not a rule set for incentives, a chemical pathway, or an explanatory model of a natural regularity.[3]

Unit

One kinematic chain: rigid links joined so their relative motions are fully determined

Recovery means

Not applicable

Measured by

Described by its degrees of freedom and analysed by the positions, velocities, and accelerations its links transmit

In the philosophy of science, a mechanism is a system of parts and activities organised so that their interactions regularly produce a particular phenomenon, and to explain the phenomenon is to describe that mechanism. Machamer, Darden, and Craver's 2000 Thinking about Mechanisms set out the influential new mechanist account, defining mechanisms as entities and activities organised such that they are productive of regular changes. On this view, explaining how a nerve cell fires or how a protein is built means laying out the parts and the doings that bring the effect about. This meaning is an explanatory structure that ties parts to their operations, not an incentive rule set, a chemical pathway, or a linkage of machine parts, even though each of those can itself be described as a mechanism in this wider meaning.[4]

Unit

One mechanism schema: entities and activities organised to produce a phenomenon

Recovery means

Not applicable

Measured by

Assessed by whether the described parts and activities can be shown to produce the phenomenon, often by intervening on them