TARGET ARTICLE On Parametric Continuities in the World of Binary Either Ors Arie W. Kruglanski University of Maryland Hans-Peter Erb University of Bonn Antonio Pierro and Lucia Mannetti Universita di Roma, “La Sapienza” Woo Young Chun Hallym University This article presents conceptual arguments and empirical evidence consistent with a uni- fied conception of human judgment. It identifies several continuous parameters which in- tersections at specific values determine the judgmental impact of the information given. The unimodel serves as an overarching framework subsuming a plethora of theoretical notions and empirical findings related to binary distinctions between associative versus rule based, automatic versus deliberative, intuitive versus rational, heuristic versus sys- tematic, and central versus peripheral modes of judgment. This perspective simplifies the depiction of human judgment processes and highlights its critical determinants. In this colloquium on modes of human judgment, our assigned task has been to represent the “unimodel” (Erb et al., 2003: Kruglanski & Thompson, 1999a, 1999b). Although, true to form, we describe our single-process framework in the pages to follow, we do not intend to is- sue here a general manifesto for unimodal formulations. Percy Bridgman, the Nobel Prize–winning physicist, fa- mously asserted that science consists of doing the damnedest with one’s mind, no holds barred. Accord- ingly, it seems unwarranted to decide in advance the rel- ative advantages of one type of formulation over others. The devil is in the details, after all. The utility of a scien- tific formulation is judged not by analytical canons of some sort but by what it actually delivers. Does it ac- count for prior data? Generate new predictions? Are these supported by further data? These are the questions to ask. In case of the unimodel the answers seem uni- formly positive, and this, to our mind, is this frame- work’s sole justification, or raison d’être. The Research Issue The unimodel addresses the conditions under which the “information given” affects judgments. This ques- tion is immanent to numerous prior theories of social cognition. Influential models of persuasion (Chaiken, Liberman, & Eagly, 1989; Petty & Cacioppo, 1986) in- quired, when do message arguments, versus peripheral or heuristic cues, impact opinions and attitudes? Con- ceptions of impression formation (Brewer, 1988; Fiske & Neuberg, 1990) inquired, when does information about social category membership or people’s “indi- viduating” attributes affect person perception? Notions of judgment under uncertainty (Kahneman, 2003; Kahneman & Tversky, 1973; Tversky & Kahneman, 1974) inquired, when does statistical information (e.g., about base rates, sample sizes, or variability) impact likelihood estimates? Models of causal attribution (Lieberman, Gaunt, Gilbert, & Trope, 2002; Trope & Alfieri, 1997) asked, when is context information in- corporated into causal judgments, and so on. Often, the answers assumed the form of various dual-mode formulations. Within each theoretical model, the two proposed modes were assumed to qual- itatively differ from each other, and the dual-mode sets differed across the models. Petty and Cacioppo’s (1986) Elaboration Likelihood Model distinguished between central and peripheral modes of persuasion, whereas Chaiken, Lieberman, and Eagly’s (1989) Heu- ristic-Systematic Model distinguished between sys- tematic and heuristic modes. Fiske and Neuberg’s Psychological Inquiry 2006, Vol. 17, No. 3, 153–165 Copyright © 2006 by Lawrence Erlbaum Associates, Inc.