晚明黨爭之劇，常被公認為明亡主因之一，而晚明黨爭之起，則始於「東林」人士的論政爭議。然引發「東林」陷入朝野爭議之人，卻是研究者鮮少專論的鳳陽巡撫李三才。李三才因任官淮陽期間政績斐然，得到同僚與百姓的認同而屈起;其後又因礦稅事件中的直言上疏，讓他在朝野清流間聲勢大振，地位鵲起。再加上李三材善用輿情，交遊南北，來往士林、高談闊論的作風，更讓他晉身大僚、涉入朝議，甚至在朝野派系的矛盾和對立中而爭議不斷。 在輿論支持的效應下，李三才拉攏士人、領導群議而逐漸形成一股新興的輿論風潮;然其依恃輿論、大言朝政的作風，又使自己屢屢成為朝野議論的焦點，造成政治形象與評價的錯亂，在各家評論中呈現兩極化的看法。至此，晚明士原意監督朝廷、封駁政事的輿論功能逐漸喪失殆盡，取而代之的則是議論不休的黨論門戶之爭。

The drastic faction fights in the late Ming Dynasty is publicly recognized to be one of the main reasons for its destruction. The origin of faction disputes in late Ming Dynasty stems from the controversial of discussing politics by “Tung-Lin” people. However, the person who aroused “Tung-Lin” to be stuck into the dispute between the government and people is Li San-ts’ ai, a governor of Feng-Yang who is seldom discussed by scholars. When he was an official at Huai-Yang, his administrative achievements was outstanding, which was recognized by the colleagues and the common people, so his position was rising. Afterwards, due to the event of minerals tax, he submitted an appeal straight so his influence among the government, people and intellectuals increased a lot and his position is highly raised. In addition, Li San-ts’ ai was good at utilizing public sentiments, socializing everywhere, making friends with the intelligentsia and his freely-talking style makes him step into the court, even makes him a controversial person among the ruling party and opposite party. By the influence of broadcasting of public opinions, Li San-ts’ ai lot close to intellectuals and led group discussions to become a newly rising direction of public opinions gradually. Nevertheless, his style of taking advantage of public opinions and freely talking about court politics makes him a frequent dispute focus by the government and people and causes confusion of political image and appraisal. The commentary by each faction is inclined to two extremes. Consequently, in the late Ming Dynasty, the function of public opinions for purpose of supervising the court, discussing political affairs by the intellectuals is almost vaporized. In instead, the biased controversies among different factions cannot be stopped.