演讲稿

No man can fully grasp how far and how fast we have come, but condense, if you will, the 50,000 years of man's recorded history in a time span of but a half-century. Stated in these terms, we know very little about the first 40 years, except at the end of them advanced man had learned to use the skins of animals to cover them. Then about 10 years ago, under this standard, man emerged from his caves to construct other kinds of shelter. Only five years ago man learned to write and use a cart with wheels. Christianity began less than two years ago. The printing press came this year, and then less than two months ago, during this whole 50-year span of human history, the steam engine provided a new source of power. Newton explored the meaning of gravity. Last month electric lights and telephones and automobiles and airplanes became available. Only last week did we develop penicillin and television and nuclear power, and now if America's new spacecraft succeeds in reaching Venus, we will have literally reached the stars before midnight tonight.
没有人能够完全明白我们已经走了多远，走得多快，但是如果你愿意，可以把人类有史以来的5万年浓缩成半个世纪的时间跨度。在这个时间跨度下，我们对于开始的40年知之甚少，只知道在这40年的最后人类学会用兽皮遮体。然后，大约10年前，根据这一标准，人类走出洞穴，开始建造其他类型的住房。只有5年前的人类才学会了写字和使用有轮子的车辆。基督教出现还不到两年。今年出现看印刷机，不到两个月前，在人类历史的整个50年跨度中，蒸汽机提供了一种新能源。牛顿研究出重力的意义。上个月电灯、电话和汽车、飞机都可以使用了。仅仅上周，我们就发明了青霉素，电视机和核能，而现在如果美国飞往金星的新的宇宙飞船成功，我们真能在今晚午夜之前到达星星之上。
This is a breathtaking pace, and such a pace cannot help but create new ills as it dispels old, new ignorance, new problems, new dangers. Surely the opening vistas of space promise high costs and hardships, as well as high reward.
这是激动人心的一步，但这一步在驱除旧弊病的同时，也会产生新的弊病、新的无知、新的问题与新的危险。航天事业战线的远景当然是成本高，但是回报也很丰厚。

背景资料

姓名：约翰·菲茨杰拉德·肯尼迪（John Fitzgerald Kennedy）
性别：男
职业：总统
国籍：美国
党派：民主党
出生日期：1917年5月29日
毕业学校：哈佛大学
成功点睛：积极变革，勇于打破常规，推动探索未知世界。
荣誉：美国历史上通过选举产生的最年轻的总统；1956年发表《当仁不让》，出版后成为美国畅销书，并在1957年获普利策传记文学奖。

The greatest knowledge increases, the greater our ignorance unfolds.
我们学到的知识越多，认识到的无知就越多。——约翰·肯尼迪