A mental model is a representation of an aspect of reality in the mind of a human (or other thinking) being. The extent to which a mental model captures the targeted aspect of reality may be formally defined as mutual information. Mutual information between a mental model and the object of modelling is the adequation of the model to its object. There is no reason to assume that mental modelling is qualitatively different from modelling in general.
Consistency with Reality
Mental models need to be consistent with some aspect of reality. Inconsistency may result from flaws in the model, e.g.:
- intrinsic logical inconsistency,
- incomplete or inadequate perception of the aspect to be modelled,
- wrong claims / assumptions about the domain of adequacy (validity) of the model.
In discourse, inconsistency may also be perceived due to
- misunderstandings about the object of modelling,
- misunderstandings about the model itself.
When perceiving a model to be inconsistent and thus "unrealistic", it is important to discern which of the above causes lead to the inconsistency.
Mental Model of a State of Reality
Mental models may represent aspects of actual states of reality in the past, present or future. Predictions are mental models of anticipated future states of reality.
Alternatively, mental models may represent states of reality that do not exist, and may never exist. These are known as utopias, desiderates, visions etc.
Mental Models as a Basis for Defining / Explaining Pain
Pain may be explained as a result of divergence between the actual state of reality and the desired state.
Mental Models and Desires for Change
Divergence between the actual and the desired state of reality results in a desire to transform the actual state into a desired state.
It is important to determine the desired state before committing to change as an objective to be achieved.
Mental Models and Democracy
The idea of democracy is (often implicitly) based on the assumption that its constituents (i.e. voters) have at least a partially adequate model of reality.
Voters need to understand, in the sense of being able to mentally model, the policies proposed by candidates. In fact, it would probably be better to consider policies, or the principles underpinning them, to be the primary candidates in democratic elections.
"Change" in Politics
Where the current political state is perceived to be unsatisfactory, "change" per se may be perceived as an attractive political programme. This has recently (August 2009) been quite successfully exploited by the Democratic Party in the USA, and in the UK, the Conservative Party tries the same (personally, I find the slogan "Conservative - vote for change" rather paradoxical). In a much more sinister perspective, right wing populists frequently use this approach in times of crisis. As the worst case so far, this has swept the Nazis in Germany to power.