Classical aphorisms
In academia, it can be extremely refreshing when one realizes how much insight can be gained from literature which is decades old. When it comes to more general non-academic insights, the same holds for material written centuries ago.
Here is a segment of an old (and admittedly very famous) Chinese poem. The Japanese kundoku is due to Tomoyoshi Ikkai in his fantastic 1998 book entitled Kanshi Nyumon.
時曖曖其将罷兮, 結幽蘭而延佇
世溷濁而不分兮, 好蔽美而嫉妬
朝吾将済於白水兮, 登閬風而緤馬
忽反顧以流涕兮, 哀高丘之無女
時は曖曖として、其れ将に罷れんとし
幽蘭結びて延く佇む
世は溷れ濁りて分かならず
好んで美を蔽いて嫉妬す
朝に吾将に白水を済り
閬風に登りて馬を緤がんとし
忽ち反顧みて以って涕を流し
高き丘の女無きを哀しむ
Despite the passage of many centuries and innumerable technological innovations, it seems the core concerns of mankind have changed very little, a reassuring thought.