Most of the people here insist that TOS takes place in the 23rd century. Still not true. It’s definitely the late 22nd century.
Sorry, it's not definitely anything based on the internal evidence of the series.
Actually there are possible interpretations of the data in TOS that would make it certain that TOS happens in the late 22nd century.
The official
Star Trek Chronology: The History of the Future second edition describes the proceedures used in writing the chronology:
This Chronology is built on a number of basic assumptions. The first is that the original Star Trek series was set 300 years in the future of the first airings of the episodes, meaning that the first season (which aired in 1966-1967) was set in 2266-2267....
The second basic assumption is that the first season of Star Trek: The Next Generation was set in 2364, as established in "The Neutral Zone"...
Actually, in "Encounter at Farpoint", the first episode of
Star Trek: The Next Generation Riker met Data:
RIKER: Then your rank of Lieutenant Commander is honorary?
DATA: No, sir. Starfleet class of '78. Honours in probability mechanics and exobiology.
And it is certainly reasonable to deduce that Data graduated during the year 78 of an unspecified century.
In a later episode, "Datalore", it it is revealed how many years have passed since Data was found on Omicraon Theta:
DATA: I was discovered twenty six years ago.
So if Data took about four years to graduate from the Acadamy, he probably entered in year '74 of that century. If that was right after Data was discovered, the date of "Datalore" could be close to the year '99 or '00. Later it is confirmed that Data spent four years at the Academy:
LORE: Promises he later proved to be true. Which made you and me possible, brother. Our beloved father. Will I soon have a uniform like that, brother?
DATA: If you get one the way I did, Lore, it will mean four years at the Academy, another three as ensign, ten or twelve on varied space duty in the lieutenant grades.
So Data was promoted to lieutenant commander about thirteen to fifteen years after graduating in the "class of '78".
Those two facts put the date of "Datalore" somewhere in the period of about '91/'93 to '99/'00 in the calendar system used by Data in Encounter at Farpoint",
In "The Neutral Zone", the last episode of the first season of
Star Trek: The Next Generation, Ralph Offenhouse, revived after centuries of death, asks:
RALPH: What year is this?
DATA: By your calendar two thousand three hundred sixty four.
So Data tells Ralph Offenhouse that the year is 2364 by Ralph's calendar, not by Data's calendar, and not by the audience's calendar, but by the calendar used by Ralph Offenouse.
It seems to be an unstated assumption of
Star Trek Chronology: The History of the Future that all dates mentioned use the
Anno Domini calendar era. But out of hundreds of dates given in various productions, only about half a dozen are specified as dates AD or BC. Thus it is quite possible than many of the dates which are mentioned without their calendar eras being specified use different calendar eras than the
Anno Domini one.
So if the year is about 2391 to 2399 in Data's calendar, and 2364 in Ralph Offenhouse's calendar, Data's calendar should count the years from a calendar era about 27 to 35 years before the calendar era of Ralph Offenhouse's calendar. Or if the year is 2300 in Data's calendar and 2364 in Ralph Offenhouse's calendar, Data's calendar would used a calendar era about 64 years after the calendar era in Ralph Offenhouse's calendar.
In "The Neutral Zone" Dr. crusher tells Clare Raymond:
CRUSHER: About three hundred and seventy years ago, you died of a massive embolism.
So Clare Rayomd died about the year 1994 in Ralph Offenhouse's calendar. And space travel in Ralph Offenhouse's year 1994 seems to have been much more advanced than was reasonable to predict when "The Neutral Zone" was made about 6 years earlier than AD 1994. But "The Neutral Zone" doesn't give any hint that Earth already has ffaster than light warp drive in the year 1994.
Earlier in the first season, in "Haven", a Tarellian ship is detected approaching:
PICARD: Sub-warp? It's several hours away then? Let's take a look at it. Enlarge to maximum.
LAFORGE: Increasing magnification, sir.
PICARD: Mister Data, is that the trouble I believe it is?
DATA: If you mean a Tarellian vessel, sir, it is.
So Tarellian ships have such a distinctive design they can be identified on the viewscreen.
RIKER: The fact that it's travelling at its present velocity suggests a possible answer.
LAFORGE: A damaged vessel, sir. That could explain it.
RIKER: If it were unable to reach warp speed, it would have taken all these years to get here.
So Tarellian ships can travel faster than light if their warp drives are not damaged.
When Dr. Crusher tells how the Tarellians wiped themselves out with a bioweapon:
CRUSHER: The Tarellians had reached Earth's late twentieth century level of knowledge. That's all you need if you're a damned fool. A deadly, infectious virus which at that modest level of knowledge is not difficult to grow.
So according to the calendar used by Dr. Crusher in that statement, Earth already had warp drive in the late 20th century. This implies that Crusher was using a calendar with a much later calendar era than Ralph Offenhouse's calendar, so that the same year would have a much lower number in Crusher's calendar.
So I assumed that Data and Crusher used one or two calendars with later calendar eras than the calendar of Ralph Offenhouse. In later seasons I noted that various dates mentioned were more and more consistent with Ralph Offenhouse's calendar.
So I assumed that when Raymond, Offenhouse, and Clemonds returned to Earth they became celebrities, and that was used by political pressure groups hoping to have the United Earth government make Ralph Offenhouse's calendar the official United Earth calendar. And they succeeded due to fame of the revived dead persons. I took that as an instance of the official United Earth calendar changing during the course of
Star Trek: The Next Generation.
And when I looked for possible examples of different calendar eras being used in TOS I found some examples which I had not previously noticed.
So what "The Neutral Zone" establishes is that at least one episode of the first season of TNG happens in the year 2364 of Ralph Offenhouse's calendar, not that it happens in AD 2364.
If an unconscious and unstated rule in
tar Trek Chronology: The History of the Future eas that all dates are given using the
Anno Domini calendar era, then according to that assumption "Wolf in the Fold" establishes an earliest possible date for TOS.
KIRK: Computer. Criminological files. Cases of unsolved mass murders of women since Jack the Ripper.
COMPUTER: Working. 1932. Shanghai, China, Earth. Seven women knifed to death. 1974, Kiev, USSR, Earth. Five women knifed to death. 2105. Martian colonies. Eight women knifed to death. 2156. Heliopolis, Alpha Eridani Two. Ten women knifed to death. There are additional examples.
So assuming that 2156 is AD 2156, the earliest possible date for "Wolf in the Fold" and TOS is AD 2156, in the late 22nd century in the
Anno Domini calendar era.
Among the other rules used in the official
Star Trek Chronology: The History of the Future are:
When a particular event is descirbe has having taken place "about a century" before a given episode, we are in most cases arbitarily assuming that it was exactly one hundred years years ago. We realize that most people tend to round such expressions off in everday speech, but we wanted a general rule...
And:
...In a similar fashion we arbitrarily assumed that all references to numbers of years have been converted to Earth-standard years. In other worlds, when Worf says something happened to him ten years ago, we assume he is speaking of Earth years rather than Klingon years...
In "Where No Man Has Gone Before" Gary Mitchel shows off his memory of the book he was reading:
MITCHELL: My love has wings. Slender, feathered things with grace in upswept curve and tapered tip. The Nightingale Woman, written by Phineas Tarbolde on the Canopius planet back in 1996. It's funny you picked that one, Doctor.
DEHNER: Why?
MITCHELL: That's one of the most passionate love sonnets of the past couple of centuries. How do you feel, Doctor?
So if Tarbolde wrote "Nightingale Woman" in English on the Canopius planet in 1996, that would imply that Earth had warp drive by 1996 and had reached distant stars by then.
Mitchell also says that 1996 was a past year during "the past couple of centuries". A couple is a pair, two. So the date of "Where No Man Has Gone Before" should be sometime between 1997 and 2196.
The first words of "Where No Man Has Gone Before" are:
Captain's log, Star date 1312.4. The impossible has happened. From directly ahead, we're picking up a recorded distress signal, the call letters of a vessel which has been missing for over two centuries. Did another Earth ship once probe out of the galaxy as we intend to do? What happened to it out there? Is this some warning they've left behind?
So the SS
Valiant has been msising for over two centuries by 1997 to 2196. Thus Earth must have had warp drive and interstellar travel sometime before the SS
Valiant left, which was over 200 years before sometime between 1997 and 2196. Thus Earth had warp drive by sometime in the period of about 1797 to 1996. Thus we might suppose that Mitchell was using a calendar with a calendar era similar to the one Dr. Crusher used in "Haven", when she implied that Earth had warp drive during the late 20th century of that calendar.
But using the unconscious assumption that all dates are given using the
Anno Domini calendar era, "Wolf in the Fold" and "Where No Man has Gone Before" would prove that TOS happens sometime between AD 2156 and AD 2196.
Assuming that TOS could happen in an alternate universe where the first manned moon shot happened at a different date than in our universe, there would be no proof that "Tomorrow is Yesterday" has to happen in July, 1969:
MAN [OC]: This is the five thirty news summary. Cape Kennedy. The first manned Moon shot is scheduled for Wednesday, six am Eastern Standard Time. All three astronauts who are to make this historic
(Kirk signals it cut off)
KIRK: Manned Moon shot? That was in the late 1960s.
SPOCK: Apparently, Captain, so are we.
KIRK: What?
SPOCK: Whiplash propelled us into a time warp, Captain. Backward. Exact chronometer readings in a few moments.
.
So the late 1960s would be1965 to 1969. Later in the episode Colonel Fellini threatens Kirk:
FELLINI: All right, Kirk. Maybe this will make you laugh. Sabotage, espionage, unauthorised entry, burglary. How are those for starters? And I can think up lots more if you don't start talking.
KIRK: All right, Colonel. The truth is, I'm a little green man from Alpha Centauri. A beautiful place. You ought to see it.
FELLINI: I am going to lock you up for two hundred years.
KIRK: That ought to be just about right.
Someone who takes Kirk's quip seriously and follows the rule that two centuries equals exactly two hundred years should believe that the part of "Tommow is Yesterday" set in Kirk's era should be sometime between 2165 and 2169.
In "The Savage Curtain" Scott argues that the image of Lincoln can't possibly be the real Abraham Lincoln.
SCOTT: Lincoln died three centuries ago on a planet hundreds of light years away.
SPOCK: More that direction, Engineer.
So Spock corrects Scott about the direction to Earth, not about the time since Lincoln died
According to the rule that "three centuries ago" equals exactly 300 years ago, "The Savage Curtain" should happen in 2165.
So "Wolf in the Fold" and "Where No Man Has Gone Before" put TOS between 2156 and 2196, and "Tomorrow is Yesterday" and "The Savage Curtain" seem to put TOs in 2165.
Thus the only way to make TOS happen after the late 22nd century is to discard some of the assumptions made by
Star Trek Chronology: The History of the Future. And if you do that, you might as well also discard the assumption in
Star Trek Chronology: The History of the Future that TOS happens from 2266 to 2269, thus making it psosible for TOS to happen in the earlier 23rd century or even in the 22nd century.
Thus, depending on the assumptions that someone makes, it is possible to prove that (using certain assumptions) TOS must happen in the late 22nd century.
