They say we tend to view the past through rose-tinted spectacles but it seems that is far from a universal rule. According to psychologists in America our views on our past and future happiness change as a function of where we are in our lives.

From a survey of over 3000 American adults conducted at two time points spaced nine years apart, Margie Lachman and colleagues found that younger and middle-aged people tended to underestimate their past happiness and to overestimate their future happiness - probably because to do so helps motivate them to strive for a better life.

By contrast, older people (aged over 65) were more accurate in recalling their prior and future life satisfaction - in this case, to do so probably reflected their need to accept their life as it had been lived, combined with their greater understanding of our capacity to adjust emotionally to whatever life throws our way. Indeed, in line with the predictions of the older participants, most people's life satisfaction, in this study and others, actually changes very little through the years (in Western democracies, at least).

Lachman's team also looked out how adaptive it was for people to have either rose-tinted or darkly clouded views of their past and future. The results showed that at whatever age, it is beneficial to have a more realistic view of the past and future. Those participants who more accurately perceived their past and future happiness tended to suffer less depression and enjoy better health.

"The young have an illusion of continued improvement, seeing the past as worse than it really was and the future as better than it turns out to be," the researchers said. "This illusion is consistent with their motivational orientation toward continued growth and gains."

有人說，我們傾向于對過去的事物持積極樂觀的態度，不過現在看來，這還遠未成為一條普遍規律。根據美國心理學家們的發現，我們對過去和未來是否幸福的觀點的變化取決于我們在人生旅途中的位置。

對超過3000名美國成年人，在相隔九年的兩個時間點上進行的一次調查中，瑪吉·拉克曼（Margie Lachman）和同事們發現年輕人和中年人傾向于過低評價他們過去的幸福，而對未來的幸福估計過高——很可能是因為這么做能讓他們擁有追求更好生活的動力。

相比之下，老年人（超過65歲）在描述他們過去和未來生活的滿意程度時更加準確——在這個案例中，這么做或許反映出他們需要承認自己的生活已經成為過去，以及他們對生活旅途中出現任何障礙時應具有的情緒調節能力有了更深刻的理解。事實上，與這些老年人參與者的預見一致，大多數人的生活滿意程度，在這個和其他研究中，經過多年也鮮有改變。（至少在西方民主國家是如此）

拉克曼的團隊還查明了人們對過去和未來持有的樂觀或悲觀態度有多大的適用性。結果顯示，無論在什么年齡段，對過去和未來都持現實主義的態度是有利的。那些能更加準確評價自己過去和未來幸福程度的人，其憂傷更少，身體更健康。

“年輕人幻想著生活能連續不斷地改善，將過去看的比其實際更糟糕，又把未來想的比其實際更美好，”研究者們說，“這個幻想與他們充滿動力的目標——持續的成長和收獲——是并行一致的。”