《资治通鉴·汉纪·汉纪四十三》
江京对阎显说： 北乡侯的病不愈，继位人应该按时确定，何不及早征召诸王之子，从中选择可以继位的人？ 
江京谓阎显曰： 北乡侯病不解，国嗣宜以时定，何不早征诸王子，简所置乎！ 显以为然。
Jiang Jing said to Yan Xian: The Marquis of Beixiang's illness has not improved, the successor should be decided soon, why not summon the emperor's sons and select a successor from among them?
<s>[INST] Kindly elucidate the central themes in this passage in English: 江京谓阎显曰： 北乡侯病不解，国嗣宜以时定，何不早征诸王子，简所置乎！ 显以为然。 [/INST] Jiang Jing said to Yan Xian: The Marquis of Beixiang's illness has not improved, the successor should be decided soon, why not summon the emperor's sons and select a successor from among them?</s>
Kindly elucidate the central themes in this passage in English: 江京谓阎显曰： 北乡侯病不解，国嗣宜以时定，何不早征诸王子，简所置乎！ 显以为然。
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Jiang Jing said to Yan Xian: The Marquis of Beixiang's illness has not improved, the successor should be decided soon, why not summon the emperor's sons and select a successor from among them?
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