A specific model is selected every time it is used, and usage implies some degree of belief in the model. Belief can range from full acceptance to a suspension of disbelief, and so can be described as a scale of certainty.[1] This corresponds to the previously discussed grammatical system of modalisation (eg Halliday 1985), the region of uncertainty between ‘yes’ and ‘no’, as set out in the table below.
congruent | metaphorical | |||
subjective | objective | subjective | objective | |
high | must | certainly | I know that… | it’s certain that… |
median | would | probably | I believe that… | it’s probable that… |
low | might | perhaps | I suspect that… | it’s possible that… |
Table 11.1 The Dimensions Of Modalisation
The table shows that statements of personal belief, from the high value ‘I know’ to the median value ‘I believe’ to the low value ‘I suspect’, are subjective metaphorical variants that separate the proposition in question from the modalisation value. The modalisation (probability) is rendered as a mental process and proposition as a metaphenomenon projected from that mental process.[2]
Thus, from this perspective, belief in a model is an interpersonal stance towards that model. As such, belief, and therefore the selection of models, involves the users of models acting upon each other in ways that either increase or decrease the certainty of potential users towards specific models, and therefore, the probability that such models will be used.
Footnotes:
[1] As Halliday (1994: 362) points out:‘we only say we are certain when we are not.’
[2] See Halliday & Matthiessen (2004: 440-1).