Structures and strategies: Where are we now?

Summary

Psychological opinion tends to sway between a view that people are almost infinitely flexible and a view that there are definite and unchangeable fundamental mechanisms that always work in the same way and set limits of flexibility. A popular compromise has been to suppose that ‘lower’ mechanisms are as determinate as typewriters, while ‘higher’ ones are unanalysable, autonomous, and perhaps even beyond scientific enquiry. The point of view in this paper favours a different compromise; very early and elementary operations are thought to be done in different ways, depending on the goals and experience of the person. There is, however, a good deal of constraint, which allows laws and principles to be laid down. Yet, there is also a degree of strategic flexibility in the operations actually performed that goes further than would be allowed by theorists of a different persuasion. The selective operations of attention are not due to unalterable mechanisms, nor does there seem to be convincing evidence of universal and invariant computation of all aspects of the input. What is computed, briefly, is the minimum necessary to perform the task before the person.