Coincidentally, just this morning—shortly before I wrote a response to someone's question related to Taoism here (The Role of Physical Cultivation and Energy)—John Tan shared a video that relates with Taoism.
03 MARCH 2026
John Tan: https://v.douyin.com/u6Ra8temH18/ This is about Taoism 玄关... If you have time, listen to the descriptions. In my opinion, it is very similar to the experience of anatta and points out certain critical aspects that are worth taking note of. So, although the descriptions and narration may sound a bit mystical and cryptic, it is worthwhile to listen to it.
21 AUGUST 2009
Thusness: Back home. Tao does not really actually source. It is the way of life of anatta. Though some people think so.
AEN: I see. Hari kept quoting this part which he thinks is "reified" :P
"There was something undefined and complete, existing before Heaven and Earth. How still it was, how formless, standing alone and undergoing no change, reaching everywhere with no danger of being exhausted. It may be regarded as the mother of all things. Truthfully it has no name, but I call it Tao"- TTC, chapter 25
Thusness: Longchen is not experiencing it wrongly, just that when the grandeur is over and yet before the natural state, he seems to be a bit discouraged. I too have this experience before. Once anatta is experienced naturally, it will be over. :)
AEN: I see.
Thusness: He has to read Chuang Tzu and Lieh Tzu also. Anyway, there is no point kept talking on something you are not sure or have not even put in effort in it.
AEN: I see.
Thusness: Do you bring out the part where Buddha said about the unconditional Self and said Buddha is referring to Brahman? So don't just comment on something you do not know. Otherwise, there is no difference from others. In the Mahanirvana sutra, the idea of Self is all around yet Buddhists have been trying to educate people on the right view of it. Similarly, do not jump into conclusion on stuff you are unsure.
AEN: I see.
23 AUGUST 2009
Thusness: I was reading through the Tao Bums discussion. Few hundred pages to read... One thing I realized is when you cut and paste what I said, you did not reference which phases of insight I am referring to.
AEN: Back. I see.
Thusness: What do you understand by Tao?
AEN: I think Tao is just everything happening naturally?
Thusness: Not good enough, but is better than treating it as a metaphysical essence.
AEN: I see.
Thusness: There is no emphasis about Awareness, luminosity, and this Self. What is mentioned in Dao De Jing, Zhuangzhi, and Lieh Tzu doctrine?
AEN: What do you mean?
Thusness: Have you read these doctrines?
AEN: Lieh Tzu I have never read before. Chuang Tzu only a bit. Chuang Tzu talks about clarity also I think... he uses the analogy of a mirror or water reflecting all things clearly when still.
Thusness: Read the wu wei section at https://web.archive.org/web/20200115044530/http://www.kktanhp.com/taoism_1.htm and compare it with the anatta article and tell me what you have understood.
AEN: Ok.
Thusness: Read through your conversation with Dwai, interesting. :) It will not be easy to convince him as he has gone quite far into experiencing the Self.
AEN: Back. I see. He said he experienced turiya. By the way, do you think Dwai is clear on non-dual?
Thusness: Not bad. Dwai based his experiences on Self.
AEN: I see.
Thusness: Maybe I will write a little comment on Rob Burbea transcript and relate it to Dwai. Got to think of a title.
AEN: I see.
Thusness: Have you read the Taoism article?
AEN: Yeah, I read the wu wei part and some others I'm reading. I noticed there's a lot on dependent origination also, other than anatta.
Thusness: Read the wu wei and see how you relate to the experience of anatta on Zhuangzhi and Lieh Tzu. Then tell me what you understand from there.
AEN: Ok. The emphasis on the flow is so that one doesn't resist or make artificial effort trying to manipulate things, but see that everything is just happening on its own accord due to dependent origination without a separate entity?
Thusness: Don't think about Buddhism first. They are not talking about Buddhism.
AEN: I see.
Thusness: However, the descriptions are?
AEN: What do you mean?
Thusness: What are they describing?
AEN: They're describing non-dual?
Thusness: What Dr. Tan is trying to say about Zhuangzhi chapter 6, yes. That is precisely the experience of non-duality. And what does it mean?
AEN: Wu wei is non-dual action?
Thusness: What is the characteristic?
AEN: Just direct experience without experiencer-experienced split?
Thusness: Yes, and without the experiencer-experienced split, what is it?
AEN: Just experiences and feelings and whatever is happening? Everything just is.
Thusness: No good, no good.
AEN: I see. Everything is just consciousness? As in conscious as it is, not as observer. Everything is like self-so and happening by itself.
Thusness: Worse.
AEN: I see.
Thusness: Read the paragraph on Pu Liang I. And read Lieh Tzu riding on the wind. When you read Taoism, whether Lieh Tzu, Zhuangzhi, Yang Zhu, or Lao Tzu, it is always about this. It is not about residing in Self. Nor residing in Tao.
AEN: I see.
Thusness: You must know what they are describing and one that is at stage is known as? (attain the Tao). So what is Tao?
AEN: Everything as it is without a self? Lieh Tzu seems like describing a state where he is no longer self-conscious. Tao is like the universe. http://www.kktanhp.com/Theravada%20Buddhism.htm -- K.K. Tan wrote on Buddhism anatta also:
"...The famous saying of Buddha: 'Within this fathom-long sentient body itself, I postulate the world, the arising of the world, the cessation of the world, and the path leading to the cessation of the world.' This sentence explains a great deal. It means that there is no Self or Atman who realises Nibbana. Everything devolves down to the five aggregates. There is no thinker: it is the thought that thinks. Similarly, it is wisdom that becomes enlightened: there is no one that became enlightened. Put it in another way, dukkha arises because of craving and it ceases because of wisdom. Craving and wisdom are within the five aggregates. And after the death of an arahant, the five aggregates become extinct: there is also no more self to be reborn! Unlike other religions, in Buddhism one can be in Nibbana while still alive. In other religions, one has to die before entering heaven...."
"...The dukkha of being is not easy to see. If you are in duality and see your-self as a separate entity from the rest of the world, you will continue to be in dukkha until you breakthrough to non-duality. The suffering and depression will not subside. .."
"Man is composed of the Five Aggregates, which are 1) the body, 2) feelings, 3) perception 4) mental tendencies and 5) consciousness. Try as hard as one may, one can find no essence or a Self or an Atman in any of these constituents. He also emphasized that there is no other essence or substance outside these five constituents. These conditioned and ever changing constituents are subjected to suffering---dukkha."- Dr. Tan Kheng Khoo
AEN: You saw this article before? You saw my messages?
Thusness: What messages? K.K. Tan anatta?
AEN: Yeah. By the way, I remember last time reading Dr. Tan's early articles on Buddhism and he was basically mistaking anatta as a state of no ego or personality. I think his recent articles are very different.
Thusness: Yes, I told you it is well written.
AEN: Oh, I didn't receive. You were logging off that time, I think.
Thusness: I see. Yes, seems like his realization has deepened into anatta. And when he wrote the article on Taoism wu wei?
AEN: Also quite recently.
Thusness: Because his insight of Tao seems to have deepened too. :)
AEN: I see. Just checked, the website started in mid 2004, the Buddhism article is written in late 2005, the Taoism articles maybe around mid to late 2007.
Thusness: I see. He must have matured his experience of anatta. :)
AEN: I see. Wow, Dr. Tan Kheng Khoo is very old, almost 80 already :P
Thusness: Wow...
Soh's Comments
p.s. I asked ChatGPT on Dr. Tan Kheng Khoo's background.
ChatGPT said:
Yes — your claim is basically supported. Dr Tan Kheng Khoo appears to have been a real Singapore pathologist-turned meditation teacher, and there is credible archival evidence that he taught meditation to Lee Hsien Loong in the early 1990s. The strongest source is Singapore’s NewspaperSG archive: a 27 May 1993 New Paper item says then–Deputy Prime Minister BG Lee Hsien Loong (who will later become the third Prime Minister of Singapore) had started meditation that year and was practising one-pointed meditation under Dr Tan Kheng Khoo, identified there as a retired pathologist. A later Straits Times piece from 2024 also refers to Tan as a meditation teacher to many people, including Lee Hsien Loong.
On the medical side, he was not just a fringe spiritual figure — he had a documented pathology career. PubMed lists him as author of “Frozen section service in the general hospital, Singapore” in Singapore Medical Journal (1965), and another pathology paper in 1966. Oxford Academic also lists him with pathology credentials and affiliation to the Department of Pathology, General Hospital, Singapore, with links to the University of Singapore. A 1962 Straits Times archive item also reports Dr Tan Kheng Khoo returning from postgraduate pathology studies in Britain.
By the early 1990s, he was publicly appearing in Singapore as a meditation teacher. A 1991 NewspaperSG listing advertises a talk by Dr Tan Kheng Khoo, calling him a retired pathologist and Honorary Patron of the Buddhist Library. Separately, SMA News mentions another doctor discussing meditation with him and describes him as an experienced practitioner of Buddhist meditation.
As for what he taught, the fuller picture online mostly comes from his own website and reposted lecture-note compilations, so I’d treat this part as self-description rather than independently verified biography. Those materials show he taught samatha / one-pointed concentration, vipassana, and Theravada-related material, but also a much broader mix of esoteric topics like cosmic healing, out-of-body experience, and kundalini/qigong psychosis. So he seems to have been an eclectic spiritual teacher, not just a conventional Buddhist meditation instructor.
I also found recent Singapore sources confirming he was the late Dr Tan Kheng Khoo and tying him to the well-known Holland Park house designed for him; The Straits Times says he died in 2019, and Docomomo Singapore refers to him as late Dr Tan Kheng Khoo.
Further Investigation Options
If you want, I can do a part 2 next and dig specifically into:
- his meditation lineage / influences
- his archived writings and teachings
- whether he was connected to Thai forest / Tibetan / Buddhist Library circles
- or a timeline biography of his life in Singapore.