Editing Argumentation theory (section)

==Psychological aspects==
[[Psychology]] has long studied the non-logical aspects of argumentation.  For example, studies have shown that [[Ad nauseam|simple repetition of an idea]] is often a more effective method of argumentation than appeals to reason.  [[Propaganda]] often utilizes repetition.<ref>Jacques Ellul, ''Propaganda'', Vintage, 1973, {{ISBN|0-394-71874-7}} {{ISBN|978-0394718743}}.</ref> "Repeat a lie often enough and it becomes the truth" is a law of propaganda often attributed to the [[Nazism|Nazi]] politician [[Joseph Goebbels]]. Nazi rhetoric has been studied extensively as, inter alia, a repetition campaign.

Empirical studies of communicator credibility and attractiveness, sometimes labeled ''charisma,'' have also been tied closely to empirically-occurring arguments. Such studies bring argumentation within the ambit of persuasion theory and practice.

Some psychologists such as William J. McGuire believe that the [[syllogism]] is the basic unit of human reasoning. They have produced a large body of empirical work around McGuire's famous title "A Syllogistic Analysis of Cognitive Relationships". A central line of this way of thinking is that logic is contaminated by psychological variables such as "wishful thinking", in which subjects confound the likelihood of predictions with the desirability of the predictions. People hear what they want to hear and see what they expect to see. If planners want something to happen they see it as likely to happen. If they hope something will not happen, they see it as unlikely to happen. Thus smokers think that they personally will avoid cancer, promiscuous people practice unsafe sex, and teenagers drive recklessly.