I want to jump in here and beg you to drop this tangent about thoughts and how real they are. It seems like a desperate grasp at being right in some way, but it’s a way that doesn’t matter.
There are posters here, one in particular, that like to use, "But it's not real." as a means of dismissing the other side.
It cannot
possibly be dismissal of anyone's RPGing to observe that the things that RPGers imagine in the course of play are not real. Anymore than it is dismissive of LotR to note that JRRT made it all up (except for some of the linguistic elements that he derived from Old English and Gothic).
What I am critical of is
accounts of the process of play that assert or imply that the fiction is real. Typically this is done in an attempt to deny that the GM is exercising agency in making up fiction. Which is utterly bizarre: the first thing that you learn about GMing, if you read Moldvay Basic or Gygax's AD&D rulebooks, is that the GM has to make some stuff up:
Gary Gygax, Players Handbook:
[O]ne player must serve as the Dungeon Master, the shaper of the fantasy milieu. (p 7)
Sometimes, however, because of close interaction (or whatever other reason) two or more Dungeon Masters will find that their games are compatible to the extent that participants in these individual campaigns can use the characters created in one to adventure in the others. In such cases the Dungeon Masters have created a very interesting "world" indeed, for their milieux will offer interesting differences and subtle shifts which will pose highly challenging problems to these players. (p 8)
When you go on an adventure, you, and in all probability one or more other characters, will go to explore some underground labyrinth or area of land outdoors. Your Dungeon Master will have carefully prepared a map of the place you and your party are to enter, a map showing all outstanding features of the place, with numbers and/or letters to key encounter/special interest areas. Your DM will give you certain information prior to the odventure - you might have to ask questions of the local populace, or you might have heard rumors or know of legends - so your party can properly equip itself for the expedition, hire men-at-arms, and obtain mounts or whatever in order to have the best possible chance for success . . . since none of the party will know the dungeon’s twists and turns, one or more of the adventurers will have to keep a record, a map, of where the party has been. Thus you will be able to find your way out and return for yet more adventuring. (p 101)
Do not be sidetracked. A good referee will have many ways to distract an expedition, many things to draw attention, but ignore them if at all possible. The mappers must note all such things, and another expedition might be in order another day to investigate or destroy something or some monster, but always stay with what was planned if at all possible, and wait for another day to handle the other matters. (p 109)
Gary Gyagx, Dungeon Masters Guide:
You, as the Dungeon Master, are about to embark on a new career, that of universe maker. You will order the universe and direct the activities in each game . . . (p 86)
You are probably lust learning, so take small steps at first. The milieu for initial adventures should be kept to a size commensurate with the needs of campaign participants - your available time as compared with the demands of the players. This will typically result in your giving them a brief background, placing them in a settlement, and stating that they should prepare themselves to find and explore the dungeon/ruin they know is nearby. As background you inform them that they are from some nearby place where they were apprentices learning their respective professions, that they met by chance in an inn or tavern and resolved to journey together to seek their fortunes in the dangerous environment, and that, beyond the knowledge common to the area (speech, alignments, races, and the like), they know nothing of the world. (pp 86-87)
Set up the hamlet or village where the action will commence with the player characters entering and interacting with the local population. Place regular people, some "different" and unusual types, and a few non-player characters (NPCs) in the various dwellings and places of business. Note vital information particular to each. Stock the goods available to the players. When they arrive, you will be ready to take on the persona of the settlement as a whole, as well os that of each individual therein. Be dramatic, witty, stupid, dull, clever, dishonest tricky, hostile, etc. as the situation demands. The players will quickly learn who is who and what is going on - perhaps at the loss of a few coins. Having handled this, their characters will be equipped as well as circumstances will allow and will be ready for their bold journey into the dangerous place where treasure abounds and monsters lurk. . . . The general idea is to develop a dungeon of multiple levels, and the deeper adventurers go, the more difficult the challenges become - fiercer monsters, more deadly traps, more confusing mazes, and so forth. This same concept applies to areas outdoors as well, with more and terrible monsters occurring more frequently the further one goes away from civilization. (p 87)
Tom Moldvay, Dungeons & Dragons Fantasy Adventure Game Basic Rulebook:
It is the DM's job to prepare the setting for each adventure before the game begins. . . . The dungeon is carefully mapped on paper . . . [T]he DM must be willing to spend more time in preparation than the players. . . . An adventure begins when the party enters a dungeon . . . [T]he DM describes what the characters can see. One player should draw a map from the DM's descriptions . . . As the player characters move further into the dungeon, more and more of the dungeon is mapped. Eventually, the DM's map and the players' map will look more or less alike. (pp B3-B4)
When the players have rolled up their characters and bought their equipment, the DM will describe the background of the adventure. This might include information about the place the characters start from, the name of any NPC companions or retainers they will have, and some rumors about the dungeon the party is going to explore. (p B19)
Before players can take their characters on adventures into dungeons, the DM must either create a dungeon or draw its map . . . This section gives a step-by-step guide to creating a dungeon. (p B51)
Both Gygax (DMG pp 97-100) and Moldvay (pp B59-B60) also provide examples of play, in which we see the players asking questions and declaring actions which trigger the GM to describe some of what s/he has made up.
From Moldvay, p B60:
Morgan: "Fred will force open the door."
DM (rolling): "It opens. You see a square room, 30' on a side and 20' high. Your door is in the west section of the north wall. You don't see any other exits. The room appears to be empty."
From Gygax's DMG, p 99:
OC: "Wait! If those fish are iust blind cave types, ignore them, but what about the stone formations? Are any of them notable? If so, I think we should check them out."
DM: "Okay. The fish are fish, but there is one group of minerals in the deepest part of the pool which appears to resemble a skeleton, but it simply - "
OC: "If the pole will reach, I'll use the end to prod the formation and see if it is actually a skeleton covered with mineral deposits from the water! I know the Shakespearean bit about a 'sea change'!"
DM: "You manage to reach the place and prodding it breaks off a rib-like piece. You see bone beneath the minerals. As you prod, however, a piece of the formation is caught by the current - a cylindrical piece about a foot long - and it rolls downstream."
In that last bit from Gygax, we (as readers of the DMG) know that the GM has referred to the notes that Gygax modelled for use earlier (DMG p 96):
THE LIMED-OVER SKELETON OF THE ABBOT is in this pool of water, but it appears to be merely a somewhat unusual mineral formation. Clutched in the bony fingers is the special key which will allow the secret door at location 28to open to the treasury room (29.) rather than to the steps which lead down to the caverns (steps down at 30). If the remains are disturbed in any way, a cylindrical object will be noticed, the thing being dislodged from where it lay by the skeleton, and the current of the stream carrying it south (downstream) at 6” speed.
None of this should be remotely controversial: the GM makes up some stuff (canonically, a dungeon with map and key) and the players declare actions for their PCs (canonically, involving interaction with the architecture, fittings and contents) and the GM narrates stuff - some of that is what s/he already made up, and some of that is extrapolated therefrom based on the details of what the players say their PCs are doing.
The idea that the rooms, the creatures, the cave-fish, the limed-over abbot skeletons, etc are
real is just bonkers!