Dogen (道厳 Dōgen) was a member of the Others and master of the Temple. He was drowned in the spring by Sayid, who was persuaded to do so by the Man in Black. Dogen preferred to speak in Japanese with the aid of his translator, Lennon, who indicated that Dogen was the only person capable of keeping the Man in Black out of the Temple. Once Dogen was murdered, the Man in Black entered the Temple as a pillar of smoke and massacred the Others who chose to keep their allegiance with Jacob.
Before the Island
According to Dogen, he was a very successful banker in Osaka before coming to the Island. He had a family, including a son. One day, Dogen received a promotion at work. He and his friends went out to celebrate, but Dogen drank too much. Under the influence, Dogen picked up his son from playing baseball, and got into a terrible car accident. Though he himself survived, his son was seriously injured and in critical condition. While his son was in the hospital, an individual named Jacob approached Dogen and said that he would heal his son if Dogen came to the Island to work for him. Dogen accepted this offer, but never saw his son again. Leaving Osaka forever, Dogen took his son's baseball with him as a keepsake. ("Sundown")
On the Island
2007 (Season 6)
When Jack, Kate, Hurley, Jin, and the injured Sayid arrived at the Temple, Dogen ordered them to be shot for trespassing. But when Hurley announced that Jacob sent them, Dogen hesitated. To prove what he said was true, Hurley gave the guitar case to Dogen; Dogen opened it to see an ankh in the guitar case. Immediately and heedless of Hurley's protests, he smashed the wooden ankh in two and pulled a list from it. Looking at the list, he asked the names of the group members, and also several others not present. Dogen then gave instructions for Sayid to be brought to a spring within the Temple. Sayid was pronounced dead by Dogen after they were unable to revive him.
In a separate room within the Temple, which appeared to be his office, Dogen received the news from Hurley that Jacob had died. Dogen swiftly ordered the Others to get into position and to protect the Temple from the Man in Black. ("LA X, Part 2")
- Note that some of items shown in this room include balancing scales, a mortar and pestle, a baseball, black and white stones -- all of which are the same as or similar to items shown in the Cliffside cave.
Later, Lennon informed Dogen that Sayid had come back to life. In response, Dogen summoned Sayid to that same room, where he began to torture him under the eventual pretext that it had been a test. After Sayid returned to his friends and told them about his ordeal, Jack angrily demanded to know why Sayid had been tortured. Dogen denied having done so, and asked Jack to give Sayid a pill which would, according to him, heal Sayid of his infection. Jack refused to do so without first knowing what was in the pill, and attempted to swallow the pill himself, but Dogen stopped him, forcing him to cough it back up. Dogen then reluctantly revealed that the pill's contents were poison. There was a darkness, he told Jack, spreading throughout Sayid's body, and once it reached his heart, he would be forever changed. Dogen went on to reveal that this same thing had afflicted Jack's sister, Claire. ("What Kate Does")
Later, Dogen caught Hurley poking around in a tunnel. He told him to return to the courtyard. Hurley, under the guidance of Jacob's spirit, told Dogen that he was a candidate, so he could do what he wanted. He told Dogen to go back to the courtyard. With this, Dogen said something in Japanese, (Translation: "You're lucky that I have to protect you. Otherwise I'd have cut your head off.") and left. ("Lighthouse")
Dogen joined Jack who was wandering outside the Temple and said that he was afraid Jack had left. Jack asked whether leaving was an option to which Dogen replied that "everything is an option". He afterwards asked Jack whether his friends were coming back and Jack answered that they were probably not.
Once alone, Sayid confronted Dogen with questions. Dogen explained the nature of the machine as something that gauged the morality of an individual (whether they were good or evil). Dogen explained that Sayid was evil and would be better off dead. The hostility between the two sparked into a fight. Dogen had the opportunity to kill Sayid, but seeing his son's baseball made him stop. Dogen banished Sayid and told him to leave the Temple at once.
However, everything changed for Dogen when Claire mysteriously returned to the Temple with a message from the Man in Black. Claire explained that the Monster wanted to speak with Dogen, who refused. Claire suggested that he send someone that the Monster would not kill, so Dogen revoked Sayid's banishment and sent him in his stead.
After Sayid's meeting with the Man in Black, he returned with yet another message: everyone was to leave the Temple by sundown or die.
Sayid later confronted Dogen at the pool. He asked Dogen why he spared his life earlier that day. Staring at the baseball that he was holding in his hand, Dogen did not answer the question directly, but explained the circumstances that brought him to the Island. Dogen concluded by asking Sayid if he would stay in the Temple or leave with the Man in Black. Sayid chose to stay, but unexpectedly attacked and killed Dogen by drowning him in the pool. When Lennon arrived to discover that Dogen was dead, he panicked and told Sayid that Dogen was the only thing keeping the Monster out of the Temple. Sayid already knew this and killed Lennon as well. The Monster then attacked the temple unhindered. ("Sundown")
Dogen was present in Los Angeles in 2004, alongside his son, with whom he appeared to have a good relationship. He and his son attended David Shephard's piano recital at Williams Conservatory, and praised David's abilities. He saw Jack there, and told him it is hard to have children with that kind of talent. ("Lighthouse")
- Dōgen was the name of a prominent Japanese Buddhist philosopher, who founded the Sōtō Zen tradition. He was, for much of his life, the head of a monastery, Eihei-ji (which roughly translates to "the temple of eternal peace").
- The historical Dōgen died on September 22, 1253, the same calendar date as the original Oceanic Flight 815 crash. Lindelof and Cuse revealed in a podcast that this coincidence was not intentional.
- Despite being written as "Dogen" using the Roman alphabet, the official name is written in Japanese using different characters than those of the name of the Japanese Buddhist philosopher. "Do" itself is written the same way (道) as written in the name of many martial arts (Aiki-dō, Karate-dō, Ju-dō, Ken-dō) and means "the way/path of." It is also featured in such Japanese concepts as shodō, the "way of writing" (calligraphy), kadō, the "way of flowers" (ikebana or flower arranging) and Shintō, the "way of the gods" (sometimes called Shintoism in English). Interestingly, in Japanese Buddhism/Shintō divinities (which are at times malicious or evil and at times benevolent) are often said to have manifest themselves in our world in human form. The do or dō in Dōgen is also the character that is read in Chinese as Dao (or Tao), which is the root of the English word Daoism (or Taoism). This may connect with Lost's featuring of Chinese ideas (yin/yang) that are loosely related to Daoism. Furthermore, according the producers the character plays a role which has both dignity and delicacy as well (this actually refers to the "-gen" part on the name).
- The "gen" part of his name according to sources from a Japanese LOST website, is 厳 which alone means "strict, rigid, or stern", although it is supposed to be derived from the word 威厳 (igen) which means: dignity; majesty; solemnity; gravity.
- Dōgen, the Japanese monk credited with founding Sōtō Zen, wrote about time or temporality in his masterpiece, Shōbōgenzō. He attempted to conceptualize a unity of process and event, becoming and being. The argument is something along these lines: a given moment is from one perspective particular, limited, and by nature suffused with delusion, but from another perspective it is simultaneously universal, a complete manifestation of the eternal, and suffused with awakening. To put the basic theory in a nutshell and in Buddhist terms: everything is Buddha and every time is Buddha, we just do not generally recognize this.
- His name may also be a reference to the dogan in Stephen King's The Dark Tower books, as all the writers have expressed that they are major Stephen King fans, with Lindelof in particular referring to the series as his favorite books.
- Zhou Daguan is a Chinese diplomat who gave early accounts of the Temple of Angkor Wat and other temples of the Khmer region, which are similar in architecture to the Island Temple. Angkor Wat is located on a mountain and may have been a funerary temple. The design of the temple also includes an inner pond.
- On different occasions, Hiroyuki Sanada has stated Dogen has been living on the Island for about 20 years. and for just over 15 years. 
- Dogen is fluent in English and Japanese, but prefers to speak in Japanese with a translator. He does this to maintain his philosophy that he needs to distinguish and distance himself from the people he leads, making it easier for them when he makes a decision that they don't like. Additionally, he claims to prefer Japanese because he simply doesn't like "the way English tastes on [his] tongue", but he may have been saying this merely to keep from admitting his true purposes.
- Dogen has been referred to by executive producer Carlton Cuse as the "Temple Master",  a title also attributed to him in enhanced episode captions. ("LA X, Part 2-Enhanced")
- Out of all the main characters, Dogen met Jack, Kate, Jin, Hurley, Sayid, Miles, Sawyer, and Claire.
- Although not shown on screen, it is very likely that he has met many of his fellow Others, such as Ben and Richard. Richard refers to the Temple by name when he urges Sawyer to go there, and Ben referred to Dogen by name after finding his body.
- It is possible that he also met the Man in Black given his comments regarding him and the fact that he knows he is capable of keeping him out.
- Dogen showed considerable skill in physical combat when he fought Sayid, proving able to defeat and even nearly kill him.
- Witnesses of death: Sayid Jarrah
- Last words: "It is sundown. Will you choose to stay or go?"
- For fan theories about these unanswered questions, see: Dogen/Theories
- How does him being alive keep The Man in Black from being able to enter the Temple?