• Optimism often invites more optimism
• In systems thinking, processes self-regulate by what is called 'negative feedback'.
• In a 'negative feedback' system, whenever a given trend increases regulatory factors act to reduce it.
• If it reduces too much then the same process brings it back to an optimum position.
• By contrast, 'positive feedback' works to augment a given trend.
• Therefore, when positive feedback occurs there is usually a 'runaway' or 'avalanche' effect.
• Optimism is often part of a 'positive feedback' process that spreads itself within a given group of people.
• We may therefore think of it as 'contagious'.
• Pessimism is also 'contagious', but it usually has fewer helpful outcomes.