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."

有人说，我们倾向于对过去的事物持积极乐观的态度，不过现在看来，这还远未成为一条普遍规律。根据美国心理学家们的发现，我们对过去和未来是否幸福的观点的变化取决于我们在人生旅途中的位置。

对超过3000名美国成年人，在相隔九年的两个时间点上进行的一次调查中，玛吉·拉克曼（Margie Lachman）和同事们发现年轻人和中年人倾向于过低评价他们过去的幸福，而对未来的幸福估计过高——很可能是因为这么做能让他们拥有追求更好生活的动力。

相比之下，老年人（超过65岁）在描述他们过去和未来生活的满意程度时更加准确——在这个案例中，这么做或许反映出他们需要承认自己的生活已经成为过去，以及他们对生活旅途中出现任何障碍时应具有的情绪调节能力有了更深刻的理解。事实上，与这些老年人参与者的预见一致，大多数人的生活满意程度，在这个和其他研究中，经过多年也鲜有改变。（至少在西方民主国家是如此）

拉克曼的团队还查明了人们对过去和未来持有的乐观或悲观态度有多大的适用性。结果显示，无论在什么年龄段，对过去和未来都持现实主义的态度是有利的。那些能更加准确评价自己过去和未来幸福程度的人，其忧伤更少，身体更健康。

“年轻人幻想着生活能连续不断地改善，将过去看的比其实际更糟糕，又把未来想的比其实际更美好，”研究者们说，“这个幻想与他们充满动力的目标——持续的成长和收获——是并行一致的。”