The significant inscription found on an old key---“If I rest, I rust”---would be an excellent motto for those who are afflicted with the slightest bit of idleness. Even the most industrious person might adopt it with advantage to serve as a reminder that, if one allows his faculties to rest, like the iron in the unused key, they will soon show signs of rust and, ultimately, cannot do the work required of them.

Those who would attain the heights reached and kept by great men must keep their faculties polished by constant use, so that they may unlock the doors of knowledge, the gate that guard the entrances to the professions, to science, art, literature, agriculture---every department of human endeavor.

Industry keeps bright the key that opens the treasury of achievement. If Hugh Miller, after toiling all day in a quarry, had devoted his evenings to rest and recreation, he would never have become a famous geologist. The celebrated mathematician, Edmund Stone, would never have published a mathematical dictionary, never have found the key to science of mathematics, if he had given his spare moments to idleness, had the little Scotch lad, Ferguson, allowed the busy brain to go to sleep while he tended sheep on the hillside instead of calculating the position of the stars by a string of beads, he would never have become a famous astronomer.

Labor vanquishes all---not inconstant, spasmodic, or ill-directed labor; but faithful, unremitting, daily effort toward a well-directed purpose. Just as truly as eternal vigilance is the price of liberty, so is eternal industry the price of noble and enduring success. 

在一把旧钥匙上发现了一则意义深远的铭文——如果我休息，我就会生锈。对于那些懒散而烦恼的人来说，这将是至理名言。甚至最为勤勉的人也以此作为警示：如果一个人有才能而不用，就像废弃钥匙上的铁一样，这些才能就会很快生锈，并最终无法完成安排给自己的工作。

有些人想取得伟人所获得并保持的成就，他们就必须不断运用自身才能，以便开启知识的大门，即那些通往人类努力探求的各个领域的大门，这些领域包括各种职业：科学，艺术，文学，农业等。

勤奋使开启成功宝库的钥匙保持光亮。如果休·米勒在采石场劳作一天后，晚上的时光用来休息消遣的话，他就不会成为名垂青史的地质学家。著名数学家爱德蒙·斯通如果闲暇时无所事事，就不会出版数学词典，也不会发现开启数学之门的钥匙。如果苏格兰青年弗格森在山坡上放羊时，让他那思维活跃的大脑处于休息状态，而不是借助一串珠子计算星星的位置，他就不会成为著名的天文学家。

劳动征服一切。这里所指的劳动不是断断续续的，间歇性的或方向偏差的劳动，而是坚定的，不懈的，方向正确的每日劳动。正如要想拥有自由就要时刻保持警惕一样，要想取得伟大的，持久的成功，就必须坚持不懈地努力。