中國禪宗一向被學術界認知為佛教在中國地區獨特的文化發展，而與印度禪有所不同；在日本一小分學術界人士別有用心之情況下，開始了對中國禪宗的批判，想要把中國禪宗外道化而逐出佛教之外；果能成功，將會使中國佛教失去原本獨特於全球佛教之上的勝妙。本文從中國禪宗所特有的禪宗公案為標記，探源於阿含部經典並發現阿含部經典中有許多禪宗公案。本文認為只有採用《蜜丸喻經》實證性批判的方法，才能夠正確判讀禪宗公案與佛教經論的意義。因此從實證性批判方法證明，龍樹菩薩樹立大乘佛教時期，不應該稱為「初期大乘」，而應該稱為「大乘復興」，即大乘佛教的第一次復興，才是符合歷史事實的定位。所以實證性批判方法的適用性，優先於文獻學與詮釋學的所有方法。 本文研究認為鴦掘魔羅「追佛公案」，被部分學術人士視為佛教故事而非公案，是因為此類學術人士不知禪宗一向遵守佛教隱覆說義的傳統，也因為二乘聖者不知禪宗的所悟內容，故不能了知這其實是禪宗的公案。根據鴦掘魔羅公案的研究，本文發現禪宗公案之目的都是為探求法界實相─第八識如來藏─而發起的法戰；而實證禪宗公案所獲得大乘見道的智慧，可以滅除六見處的錯誤與過失。禪宗公案是滅除六見處之法，也是為了矯正沒有實證法界實相而墮於想像猜測的斷常二見者以及二乘人。因此滅六見處是大乘見道所證，而不是二乘人所實證的內涵，也顯示大乘真實禪與二乘方便禪思的不同。 本文舉出阿含部經典中三則公案，以及一則野狐禪，證明大乘禪曾在佛世普遍宣說的歷史事實。本文以阿含部經典中另一則禪宗公案證明，佛陀親自宣說第二轉法輪「般若時」的大乘經典時，二乘人不但參與法會並且親見大乘菩薩見道公案的發生，最後結集記錄於阿含部經典中。由於阿含部經典中有大量關於大乘法義的文獻證據，因此證明大乘經典是佛陀親口宣說，並由三乘人共同見證「大乘是佛說」的歷史事實。

The academic society always regards the Chinese Chan School as a unique culture development of Buddhism in China, which is different from the Indian Chan; with some specific purposes, a few persons in Japanese academic society started to criticize the Chinese Chan School and tried to expel the Chinese Chan School from Buddhism by claiming it as non-Buddhism; if they succeeded, the Chinese Chan School would lose its supremacy, which is originally unique to worldwide Buddhism. This article uses the Chan Koans, which only exist in Chinese Chan School, as the subjects to explore its origin in the sutras of the Agama division and finds there are many Chan Koans in those sutras. This article thinks only through the method of positivist criticism in The Sutra of Honey Pill Simile can one correctly interpret the meanings of the Chan Koans and Buddhist sutras or treatises. From the method of positivist criticism, this article proves that it should not be called the ―initial stage of Mahayana when Bodhisattva Nagarjuna started the stage of Mahayana Buddhism, but called the first revival of Mahayana Buddhism, which is a correct positioning in conformity with the historical fact. Therefore, the applicability of positivist criticism method has higher priority over all methods of document study and hermeneutics. This article thinks that some academic persons regard Angulimala‘s ―Koan of Chasing the Buddha as a Buddhist story rather than a Koan because they do not know the Chan School always follows the Buddhist tradition of teaching with the true meaning hidden; it is also because the saints of Two Vehicles do not know the contents of enlightenment in the Chan School; therefore, they do not know it is in fact a Chan Koan. According to the study on Angulimala‘s Koan, this article finds that the purpose of Chan Koans are all for the dharma debate on exploring the ultimate reality of dharma-realm, the eighth vijnana Tathagatagarbha; with the wisdom of Mahayana enlightenment, which is obtained through the actual realization of the Chan Koan, the practitioners can eliminate the error and fault of the fields of six views. The Chan Koan is a method to eliminate the fields of six views; it is also a method to correct the practitioners of nihilism, eternalism, and Two Vehicles,who do not actually realize the ultimate reality of dharma-realm and fall into imagination and speculation. Therefore, eliminating the fields of six views is the realization of Mahayana enlightenment, rather than the content actually realized by the practitioners of Two Vehicles; it also manifests the difference between the real Chan of Mahayana and the expedient Chan thought of Two Vehicles. This article lists three Koans in the sutras of Agama division and one of Wild-Fox Chan to prove the historical fact that the Buddha had expounded the Mahayana Chan frequently during His lifetime. This article also proves, using another Koan in Agama division, that when the Buddha gave the Mahayana “prajna” teachings of the second round of dharma transmission, the practitioners of Two Vehicles not only attended the dharma-teaching assembly but also witnessed the occurrence of Koans about the enlightenment of Mahayana bodhisattvas; those facts were finally recorded in the sutras of Agama division. Because there is lots of documental evidence about Mahayana doctrines in the sutras of Agama division, we can prove that the Buddha personally gave the Mahayana teachings, and that all practitioners of Three Vehicles witnessed the historical fact of ―Mahayana being the Buddha‘s teaching.