Final answer:
Individuals can exhibit various attitudes towards a proposition, such as belief, doubt, or ignoring it. These attitudes are influenced by cognitive dissonance and persuasion, which can involve selective confirmation and bias.
Step-by-step explanation:
The question presented is concerned with the three relevant attitudes one can have towards a proposition after considering it. Based on the provided information, we can deduce that the attitudes towards a proposition can include believing in it, doubting it, or ignoring it. Such attitudes are shaped by a complex interplay between internal factors, like cognitive dissonance, where one experiences tension due to conflicting beliefs and external factors, such as persuasion from sources like advertising. Cognitive dissonance might compel an individual to adjust their behaviors, attitudes, or beliefs to alleviate the tension. Persuasion, on the other hand, can either follow a central route, involving the direct use of facts and information, or a peripheral route, that relies on positive associations. Individuals may also engage in selective confirmation, actively seeking out information that confirms existing beliefs and ignoring contradictory evidence, which can lead to a biased understanding of the proposition.