Research Outline

Human Decision Making - Emotions vs. Logic


To prove that most human decisions are made based on emotions, not logic. Specifically, to understand how the limbic system makes most decisions, while the neocortex only justifies the decision already made.

Early Findings

Logic vs. Emotions

  • "We are persuaded by reason, but we are moved by emotion."
  • Ninety percent of human decisions are made based on emotions. Humans use logic to justify their actions to themselves and others.
  • According to Arthur Lefford, author of "The Influence of Emotional Subject Matter on Logical Reading," people generally think their decisions are made based on facts. The study found that when "people agree with a particular message, they tend to perceive it as being more logical or rational. On the other hand, when people disagree with the message, they perceive it as an emotional plea."
  • Ninety-five percent of purchase decisions are subconscious, according to Gerald Zaltman, a Harvard Business School professor.
  • The most common emotional decision is reactive (subconscious) decision-making. It is typically very fast, as it takes at least 0.1 seconds for the rational cortex to start responding.
  • "Common emotional decisions may use some logic, but the main driving force is emotion, which either overrides logic or uses a pseudo-logic to support emotional choices (this is extremely common). Another common use of emotion in the decision is to start with logic and then use emotion in the final choice."
  • According to the neuroscientist Antonio Damasio's study conducted on people with brain injuries that damaged the part of their brains where emotions are generated, these injuries affected not only their ability to feel but also their ability to make decisions, which was seriously impaired. They were able to logically-describe what they should do, but with no rational way to decide, they were unable to make the decision.