The comprehensive analysis of public opinion requires attention to two phenomena: how citizens learn about matters that are for the most part beyond their immediate experience, and how they convert the information they acquire into opinions.

This chapter proposes a model of both phenomena. The model does not provide a fully accurate account of how people process information and form attitude statements. No model that is both parsimonious and testable on typical mass opinion data – the two most important constraints on my enterprise – could possibly do so. But the proposed model, as I hope to persuade the reader, does a plausible job of approximating what must actually occur, and a quite excellent job of accounting for the available survey evidence across a wide range of phenomena.

Having stated a model of the opinionation process in this chapter, I proceed in the rest of the book to test a series of propositions derived from the model. Some additional ideas will be needed to accomplish this, but they are few and incidental. All of the important features of my analysis derive from the model that is presented here.

SOME DEFINITIONS

I begin the statement of the model with definitions of primitive terms. The first is consideration, which is defined as any reason that might induce an individual to decide a political issue one way or the other.