Tag Archives: trust

First We Believe, Then We Evaluate

When presented with a piece of information for the first time, do we first understand the message before carefully evaluating its truthfulness and deciding whether to believe it, or do we instead immediately and automatically believe everything we read?

In an article that traces the history of this question (Descartes argued that “understanding and believing are two separate processes” while Spinoza thought that “the very act of understanding information was believing it”), an ingenious experiment conducted almost twenty years ago by Daniel Gilbert, author of Stumbling on Happiness, describes how Spinoza was correct: when we first encounter information we believe it immediately and without thought, only to fully evaluate its truthfulness moments later provided we are not distracted.

Obviously it is important to be aware of this behaviour, as to be distracted while reading critical information of questionable veracity could cause us to not evaluate it fully or at all. However this behaviour has further implications, according to the article, suggesting that this may “explain other behaviours that people regularly display”, including:

  • Correspondence bias: this is people’s assumption that others’ behaviour reflects their personality, when really it reflects the situation.
  • Truthfulness bias: people tend to assume that others are telling the truth, even when they are lying.
  • The persuasion effect: when people are distracted it increases the persuasiveness of a message.
  • Denial-innuendo effect: people tend to positively believe in things that are being categorically denied.
  • Hypothesis testing bias: when testing a theory, instead of trying to prove it wrong people tend to look for information that confirms it.

The Optimal Level of Trust

How much we trust people influences much more than just our interpersonal relationships and can even cost us a considerable amount of financial harm.

The study concluding this (pdf) suggests that too much or too little trust has a financial cost equivalent to that of not attending university and shows that if we trust too much we assume too much social risk, but trust too little and we give up potentially profitable opportunities:

Highly trustworthy individuals think others are like them and tend to form beliefs that are too optimistic, causing them to assume too much social risk, to be cheated more often and ultimately perform less well than those who happen to have a trustworthiness level close to the mean of the population. On the other hand, the low-trustworthiness types form beliefs that are too conservative and thereby avoid being cheated, but give up profitable opportunities too often and, consequently, under-perform. Our estimates imply that the cost of either excessive or too little trust is comparable to the income lost by foregoing college. Furthermore, we find that people who trust more are cheated more often by banks as well as when purchasing goods second hand, when relying on the services of a plumber or a mechanic and when buying food.

via Tim Harford