曹溪禪的開展與合流，在中國禪宗史與文化史的意涵殊大。達摩禪的不斷發展，逐漸適應而成為「中國禪」——「中印文化融合的禪」、「東方文化的精髓」。關於慧能門下曹溪禪之發展軌跡，胡適認為，「曹溪禪歸本於荷澤」，故多著墨於神會的研究。鈴木大拙聚焦論述曹溪門下的禪風，包括：（一）洪州宗、石頭宗「用經驗」的禪風；（二）洪州宗、石頭宗的「只沒禪」；（三）「用經驗」與「只沒禪」的超越之「知」。在他看來，「用經驗」、「只沒禪」，從宗教性到生活化、藝術性的表達，其思想根源是慧能的見性經驗與見性哲學。宇井伯壽以為，慧能門下曹溪禪荷澤宗、洪州宗、石頭宗各有發皇，而北宗門庭趨於衰弱，給予荷澤神會打擊的機會；至於馬祖與石頭所弘揚的南宗禪思想——「即心是佛」、「即心即佛」，實立基於青原行思與南嶽懷讓。關口真大集中亦討論荷澤宗、洪州宗、石頭宗三宗並加以比較；他依宗密《禪源諸詮集都序》的記載，發現石頭宗早期在慧能門下宗派中並不凸顯，而洪州宗與牛頭宗有合流的傾向，石頭宗與牛頭宗則思想一致。印順與上述學者最大的不同是，他認為慧能門下曹溪禪除荷澤宗、洪州宗、石頭宗外，應包括保唐宗；且曹溪門下之禪風，已有「巧說」、「破相」、「慢教」與「輕定」的格調；而曹溪禪與牛頭禪的合流，始形成禪宗的「中國化」。

The development and combination of Cao-si Zen have extremely significant meaning in the history of the Chinese Zen Master as well as the history of the Chinese culture. The continuous development and adaptation of Da-mo Zen have made it become the “Chinese Zen” —— the so-called “Zen of Indo-Chinese cultural integration,” or “essence of the Oriental culture.” In tracking the development of Cao-si Zen following and being under Huei Neng, Hu Shih thinks that “Cao-si Zen was originated from He-ze,” and thus focuses on studying Shen Huei. Suzuki Daisetsu concentrates his discussion on the Zen style of the followers of Cao Si, including: (1) Hong-jhou Master’s and Shih-tou Master’s Zen style of “using experience”; (2) Hong-jhou Zen’s and Shih-tou Zen’s Zen style of “only without Zen”; (3) Transcended “knowing” of “using experience” and “only without Zen.” To him, the thinking of “using experience” and “only without Zen,” from the religious nature to the lifelike and artistic expression, was originated from the seeing experience and seeing philosophy of Huei Neng. Ui Hakuju indicates that the Heze Master, Hong-jhou Master and Shih-tou Master of Cao-si Master, which is following and being under Huei Neng, have been developing prosperously. However, as the Northern Master declines, it gives Heze God Association a chance of making combats. As to the thinking of the Southern Master spread by Ma-zu and Shih-tou —— “referring to the heart which is just Buddha,” and “referring to the heart and to Buddha,” they are actually solidified on Sing-si of Cing-yuan and Huai-rang of Southern Mountain. Collected Works of Sekiguchi Mahiro also discusses He-ze Zen, Hong-jhou Master and Shih-tou Master and makes a comparison of these three Masters. Based on the records of Preface to the Various Zen Origins written by Zong-mi, he finds that in the early day Shih-tou Master is not an outstanding Master among the various Masters under Huei Neng, and there is a tendency of combination between Hong-jhou Master and Niu-tou Master. And the thinking of Shih-tou Master and Niu-tou Master are consistent. The greatest difference of Yin Shun’s argument from those of the abovementioned scholars is that he believes that apart from extending to He-ze Master, Hong-jhou Master and Shih-tou Master, Cao-si Master being under Huei Neng should also include Pao-Tang Master. Besides, he thinks that the Zen pattern of the followers of Cao Si has such artistic styles as “technical statement,” “spoiling of facial features,” “slow teaching” and “light decision.” Eventually, the combination of Cao-si Zen and Niu-tou Zen thus brings strong “Chinese” essence to Zen.