眾所皆知，《孟子．告子上》是關係到他的心性論，但這個理論不是本文研究的主旨。本文的主旨是探討其申雄辯家所採用的辯論方法。作者認為這一篇文章中，辯論雙方的對話蘊涵了一些論辯的謬誤，是值得我們深入探討的。我們要指出的謬誤包括邏輯層次的不清、人身攻擊代替論證的偏差、複合命題使議論混淆的失策、忽視論點之多面性的黑白辯等。讀者認清詭辯與謬誤，才不會墮入辯者的推論的錯誤與偏差，因而對正確的邏輯思考能有更靈敏的掌握。通過較完整的邏輯思維，才能夠對論辯中的義理有更透徹的辨別與理解。

The chapter “Gaozi Shang” in Mengzi is related to Mengzi’s theory of human nature. However, this paper is to discuss the ancient orators’ argumentative techniques. We have discerned some argumentative fallacies in the dialogues between Mengzi and Gaozi, which include the fallacy of mixing two different levels of argument, the substitution of character attack for persuasive reasoning, the compound of two related but different proposition, and the pitfalls of black-or-white reasoning, The awareness of these fallacies would enable the reader to reject the false arguments and to catch the aforementioned philosophical issues and propositions.