Your mood affects your judgment. When making a decision, if you’re happy at that moment, you may decide differently than if you’re upset. For instance, a judge may issue a severe judgment on a criminal defendant because his roof leaked the night before and ruined his favorite desk. The same judge may issue a lenient judgment because he’s happy about leaving on vacation the next day. (Clever people learn how to use this truth to their advantage: when needing a decision from someone, they’ll wait until the person is in a good mood before asking.)
Generally speaking, a positive mood and disposition leads to a better life and sense of well-being than a negative mood or disposition. And relative to interpersonal relationships, we prefer to spend time with people who are happy and positive rather than those who are grouchy and pessimistic.
But there’s at least one instance in which pessimism can be an asset. Being in a good mood (or by nature positive and optimistic) can make us naive and we can be easily misled. When we view life through rose-tinted glasses, our optimism can lead us to make bad decisions.
So, while it’s better to have a positive outlook on life than a negative one, be aware that positivity has a downside; it can distort our judgment. Be positive but don’t be gullible. Don’t believe everything you’re told. Don’t be swayed by charming people. Don’t be overly influenced by first impressions. Don’t be duped by misleading information.
When it comes to interpreting information and making decisions, skepticism is better than credulity. Unbridled optimism can render you naive and lead to bad decisions.