In this dissertation, I deal with the problem of presupposition projection. I mostly focus on compound sentences composed of two clauses and conditional sentences in which the second clause carries a presupposition. The central claim is that the presupposition carried by the second clause projects by default, with the exception of cases in which the presupposition entails the first clause (or, in disjunctive sentences, the negation of the first clause). In the latter cases, the presupposition should not project, since it is logically stronger than the first clause (or its negation). Thus, in conjunctions, if the presupposition projected, the speaker’s assertion of the first clause would be uninformative. As for conditionals and disjunctions, if the presupposition projected, the speaker would show inconsistency in his/her beliefs by showing uncertainty about the truth value of the first clause (or its negation). I argue that, in conditionals, this uncertainty is conversationally implicated whereas, in disjunctions, it results from the context’s compatibility with the first disjunct. I maintain that, in cases where projection is blocked, the presupposition is conditionalized to the first clause (or its negation). I demonstrate that the conditionalization is motivated in a straightforward way by the pragmatic constraints on projection just described and that, contrary to what is defended by the so-called ‘satisfaction theory’, presupposition conditionalization is a phenomenon independent from local satisfaction. / En esta tesis, trato el problema de la proyección de presuposiciones. Me centro mayoritariamente en oraciones compuestas de dos cláusulas y en oraciones condicionales cuya segunda cláusula contiene una presuposición. El argumento central es que la presuposición contenida en la segunda cláusula proyecta por defecto, con la excepción de casos en los que la presuposición entraña la primera cláusula (o, en las oraciones disyuntivas, la negación de la primera cláusula). En estos últimos casos, la presuposición no debería proyectar, puesto que es lógicamente más fuerte que la primera cláusula (o su negación). Por tanto, en las oraciones conjuntivas, si la presuposición proyectase, la aseveración de la primera cláusula por parte del hablante no sería informativa. En cuanto a las oraciones condicionales y disyuntivas, si la presuposición projectase, el hablante mostraría inconsistencia en sus creencias al mostrar incertidumbre acerca del valor de verdad de la primera cláusula (o su negación). Sostengo que, en oraciones condicionales, esta incertidumbre es implicada conversacionalmente mientras que, en las oraciones disyuntivas, resulta de la compatibilidad contextual de la primera cláusula. Mantengo que, en casos en los que la proyección es bloqueada, la presuposición es condicionalizada a la primera cláusula (o su negación). Demuestro que la condicionalización es motivada de manera directa por las restricciones de tipo pragmático descritas arriba y que, contrariamente a la idea defendida por la así llamada ‘teoría de la satisfacción’, la condicionalización de la presuposición es un fenómeno independiente de la satisfacción local de la misma.

The mere thought effect is the tendency for favorable attitudes to become more favorable and unfavorable attitudes to become more unfavorable following thought (Tesser, 1978). Changes in belief-consistency and belief-confidence mediate this effect (Tesser, Martin, & Mendolia, 1995). However, there are self-monitoring differences in the extent to which people are driven by consistency in their beliefs (Fuglestad & Snyder, 2009; Snyder, 1974). It was predicted that mere-thought and self-monitoring will interactively influence attitude polarization. We also hypothesized that the interactive effects of mere-thought and self-monitoring on attitude polarization will be mediated by belief-consistency and belief-confidence. After indicating their initial attitudes about capital punishment, participants were randomly assigned to two different opportunities for thought (i.e., 60s or 180s condition) to list all beliefs about capital punishment. Participants independently responded to the 25-item Self-Monitoring Scale (Snyder, 1974) and a measure on belief-confidence. As predicted, there was a marginally reliable significant interaction between mere-thought and self-monitoring. Low self-monitors compared to high self-monitors demonstrated more polarized attitudes when giving them more time to think about a target issue. As predicted, after controlling for belief-consistency and belief-confidence, the interaction between opportunity for thought and self-monitoring was attenuated. Limitations (i.e., problem with directionality, third variable problem, and threats to statistical validity) and suggestions for future research (i.e., conditions high self-monitors might exhibit more attitude polarization and exploring additional personality/situational moderators) were discussed.