Jovial!!

The fact that Daniil is specifically referred to as a "Bachelor" of medicine is something that was always sort of confusing to me but is actually extremely telling when put together with all the other details we get about him.

There's an excellent video essay about Daniil's character by Horror Game Analysis which goes into more detail about this [x], but he points out two things about thanatology that I think are really significant:

It was first conceptualised as a field of study in 1903 by Ilya Mechnikov, a Russian-Ukranian immunologist and microbiologist, who felt that there was not enough known about the phenomenon of death itself; and

Thanatology straddles the line between the humanities and the sciences because it's investigations grapple with the physical, psychological, socio-cultural, philosophical, and spiritual elements of death

With all that in mind and Pathologic's ambiguous time period, Daniil could very much be read as the in-game world's equivalent of Mechnikov. Despite his (sort of) alignment with the philosophically-minded Kains, Daniil is consistently shown to be very much focused on the physical components of death. He came to the town hoping that "[Simon's] tissues will help [him] defeat death." Rubin, Artemy, Victor (and Lara, Yulia, Aspity, Anna, and Clara) all need him to collect and examine blood samples for evidence of the disease. Once the plague begins, his focus in on the creation of a vaccine - a tool for immunisation - instead of a cure.

All of the evidence points to Daniil, at his core, being a microbiologist and researcher. His medical knowledge, while far above average, is highly specialised and doesn't indicate that he has any practical experience as a physician. He's not a doctor, he's a bachelor of medicine using his theoretical and academic expertise to fight an impossible disease in the only way he knows.

Now, Artemy does have some practical knowledge. Isidor taught him about the traditional medicine of the town while he was growing up before sending him to "study modern medicine in the academy" when he was 16. However, in his opening description, all we are told is that Artemy is returning from several years of "travelling from town to town learning theoretical and pratical surgery." In Pathologic Classic, Artemy is canonically 26 years old so if he spent 6-7 years travelling, his formal medical education was likely either short or incomplete. Not to mention that the emphasis on Artemy as a surgeon and menkhu (much like Daniil as a bachelor and thanatologist) implies a very specialised area of expertise which, although closely related to practical medicine, is not the same thing.

This is reinforced in a number of ways. For example, while there are multiple dialogue options which let you dismiss the town's local medical practices, they appear mostly (or only) in conversations with outsiders - responding to Daniil's admission of underestimating the value of "steppe medical knowledge" with "there's nothing medical in their knowledge" and telling Block that he has "an education in the civilized world and ha[s] forgotten two thirds of the specific local practices." Ultimately, Artemy is more consistently aligned with the Kin's more bodily approach to medicine. That distinction between Kin and Town is important, since the traditional medicines Artemy makes are not valued or trusted by townspeople and the kin refuse almost all of the modern medicine (specifically antibiotics) sold in the town.

He also seems to be either unfamiliar or seriously out of practice with the more formal language of science and medicine a university-educated physician should know. At several points, Artemy is shown to be dependent on Daniil's medical knowledge, and various members of the town poke fun at him for asking clarifying questions - Boy: "You graduated from a university and this is your question…?" Rubin: "I thought you were [away] studying." Artemy's story is about trying to fill his father's role and, while he succeeds in becoming a menkhu, his position as the town's doctor is less clearly defined even after the plague. While he begins the game with the most practical experience of the three protagonists, the fact that he's not qualified to be a physician but has to act as one is what drives his story forward.

I won't go into Clara since it's obvious she's not a doctor. If anything, she's more like a personification of a cure for this one specific disease (just like her 'twin' is the plague). She couldn't reset a bone or diognose the flu any more than she could synthesise antibiotics or distinguish between bacteria in a blood sample. Still, she's an interesting comparison point and does serve to remind the player that the protagonists don't really represent different approaches to medicine, but different approaches to healing.

The Bachelor is the modern healer of formal scientific practices who sees healing as the result of understanding the body, disease, and their interactions.

The Haruspex is the traditional healer with the spiritual or ancestral right to protected knowledge and practices who sees healing as a reflection of cultural duty, customs, and community.