田常 / Tian Chang
田常 / Tian Chang appears in 《资治通鉴·周纪》57丨古代发毒誓还有这作用？ as the 齐国 chief minister whom 子贡 / 端木赐 persuades during the effort to save 鲁国. The episode presents him as the first lever in Zigong’s chain: if Tian Chang can be moved away from attacking weak Lu, the immediate danger to Lu can be displaced into a larger strategic field.
The page is source-scoped. Tian Chang’s function in this telling is to show that successful rescue diplomacy begins by reading the decision-maker’s incentives, not by pleading for mercy in the abstract.
Qinji 130-4 reuses Tian Chang as a warning analogy inside 李斯’s memorial against 赵高. The source summary writes the name as 田恒, but the described case is the Qi minister who accumulates ruler-like favor, punishment power, and wealth before killing the ruler and taking 齐国 power. The wiki therefore links this source-scoped “田恒” form here rather than to the later anti-Qin 田横 page.