the overall framework
It has become fashionable to speak of continua, and we are thus apt to speak of a continuum of party systems. The underlying assumption is that typological constructs ignore the fluidity of reality and that the interlocking of the real world can be recaptured by postulating an endless stream of continuity. The claim is warranted, but its fulfilment demands fine discretion.
In the first place, the concept of continuum cannot remain, in a natural language, exactly what it is in mathematical language. In particular, it cannot be assumed – in the social science usage of the concept – that continua exclude discontinuity by definition. In the second place, we do not seem to be clearheaded as to how a classification relates to a continuum. When we speak of a continuum of party systems, of political systems, of regimes, and the like, we are using a shorthand expression. In effect we are confronted with two distinct logical operations: First, the determination of the polar concepts that define the continuum or, better, the dimension along which we posit a continuum (e.g., consensus-coercion, liberty-oppression, expression-repression, inclusion-exclusion) and, second, the placement of the classes, or types, at different points of the continuum so defined. Strictly speaking, it is incorrect to postulate a 'party continuum'; we can only postulate a 'conceptual continuum' along which party systems can be approximately located. The continuum is not between party systems, but between polar characteristics; and the kind of continuity or discontinuity that exists in fact among the various party systems is an empirical question that can only be settled empirically.
A third remark is in order. The reason that we are apt to underscore discontinuity is that the idea of continuum appeals to a unidirectional evolutionary optimism. More often than not, the idea that party systems are contiguous, and thereby convertible all along the line, goes to suggest that there is a 'natural' course of political development that leads – whenever it is not unnaturally deviated – to freedom, party pluralism, and democracy. Setbacks do occur, but they are only setbacks. The so-called liberalisation of Communist regimes, together with the instances of Turkey and Mexico, are highly significant cases that uphold the continuum approach; while the relapses into fascism, authoritarianism, and praetori