Gradable adjectives denote a function that takes an object and returns a measure of the degree to which the object possesses some gradable property [Kennedy, C. (1999). Projecting the adjective: The syntax and semantics of gradability and comparison. New York: Garland]. Scales, ordered sets of degrees, have begun to be studied systematically in semantics [Kennedy, C. (to appear). Vagueness and grammar: the semantics of relative and absolute gradable predicates. "Linguistics and Philosophy"; Kennedy, C. & McNally, L. (2005). Scale structure, degree modification, and the semantics of gradable predicates. "Language", 81, 345-381; Rotstein, C., & Winter, Y. (2004). Total adjectives vs. partial adjectives: scale structure and higher order modifiers. "Natural Language Semantics", 12, 259-288.]. We report four experiments designed to investigate the processing of absolute adjectives with a maximum standard (e.g., "clean") and their minimum standard antonyms ("dirty"). The central hypothesis is that the denotation of an absolute adjective introduces a "standard value": on a scale as part of the normal comprehension of a sentence containing the adjective (the "Obligatory Scale" hypothesis). In line with the predictions of Kennedy and McNally (2005) and Rotstein and Winter (2004), maximum standard adjectives and minimum standard adjectives systematically differ from each other when they are combined with minimizing modifiers like "slightly", as indicated by speeded acceptability judgments. An eye movement recording study shows that, as predicted by the Obligatory Scale hypothesis, the penalty due to combining "slightly" with a maximum standard adjective can be observed during the processing of the sentence; the penalty is not the result of some after-the-fact inferencing mechanism. Further, a type of "quantificational variability effect" may be observed when a quantificational adverb (mostly) is combined with a minimum standard adjective in sentences like "The dishes are mostly dirty", which may receive either a degree interpretation (e.g., 80% dirty) or a quantity interpretation (e.g., 80% of the dishes are dirty). The quantificational variability results provide suggestive support for the Obligatory Scale hypothesis by showing that the standard of a scalar adjective influences the preferred interpretation of other constituents in the sentence.