True or false? Chess will never be solved! why?

10^120 is only finite in a purely theoretical sense. 

It's more than the number of atoms in the universe, and by more I mean it would take about 10^40 universes worth of atoms to get there. 

#1203, #1204
The Shannon Number 10^120 is not relevant. Relevant is the number of positions, not the number of possible games. 1 e4 e5 2 Nf3 Nc6 is the same position, but a different game as 1 Nf3 Nc6 2 e4 e5, 1 Nf3 e5 2 e4 Nc6, 1 e3 e6 2 e4 e5 3 Nf3 Nc6, 1 e3 Nc6 2 e4 e6 3 Nf3 e5 etc. There are many transpositions leading to different games, but the same positions.

Many of the possible positions are not legal. Many of the legal positions are not sensible, like with 9 white queens. Many of the sensible positions are not relevant: play no role from the opening under investigation. Only like 10^19 positions are legal, sensible, and relevant. 

"so you're tellin me there's a chance"

Only 10^19? Well then... 

It isn't like a solution is just a list of all legal positions. Some games transpose but not 10^120 down to 10^19. That's not getting rid of 5/6 of the games as repetitive. That's getting rid of far more than 99.999999 of the games. With about 100 9s there. 

Also, for a solution you don't get to disregard what is "sensible" and/or "relevant." Figuring that out is kinda the point of the whole thing. 

#1207

Number of possible games: 10^120
Number of possible positions: 10^46
Number of legal positions with up to 9 chess sets: 10^44
Number of sensible positions with 1 chess set: 10^40
Number of sensible positions with 26 men: 10^38
Number of relevant positions from a 26 men starting position: 10^19

An example of an illegal position, which can play no role in solving chess.

An example of a legal, but not sensible position, which plays no role in solving chess.

An example of a 26 men starting position opening C67

Another example of a 26 men starting position opening D85

An example of a legal and sensible position, but irrelevant for both above 26 men starting positions as it can never be reached from either of them

Well, your first 2 numbers are good.

The rest are sketchy, as has been pointed out before..  You also need to define your terms better.  "9 chess sets" in English means 9 physical boards and 9 sets of pieces ...

#1209
The other numbers stem from John Tromp research,
except the number of relevant positions, estimated from analogy to Schaeffer's proof that checkers is a draw: about the square root of the number of legal and sensible positions.

Definitions:
Legal position = position that can be reached from the initial position.
Sensible position = position that can be set up using only men from 1 box of chess men, i.e. without having to borrow excess promotion pieces from up to 8 other boxes of chess men.
Relevant position = position that plays a role in the proof.

The point: each pawn move and each capture render many positions irrelevant.

#1211
Please share your methodology. Here is what I came up with.

From the initial position the 'good assistant' considers 4 top white moves: 1 e4, 1 d4, 1 c4, 1 Nf3. If black draws against all 4, then it becomes trivial to prove that black can draw against all 16 other white 1st moves as well. Say we start with 1 e4.
Now consider only the top 1 black response 1...e5. It is possible that black can draw with 1...c5, 1...e6, or 1...c6 as well, but if 1...e5 draws, then chess is solved.
Now consider the top 4 white moves: 2 Nf3, 2 Nc3, 2 Bc4, 2 d4. If black draws against all 4, then it becomes trivial to prove that black can draw against all other white 2nd moves as well. Say we continue with 2 Nf3.
Now consider only the top 1 black response 2...Nc6. It is possible that black can draw with 2...Nf6, 2...d6, or 2...f5 as well, but if 2...Nc6 draws, then chess is solved.
Now consider the top 4 white moves: 3 Bb5, 3 Bc4, 3 d4, 3 Nc3. If black draws against all 4, then it becomes trivial to prove that black can draw against all other white 3rd moves as well. Say we continue with 3 Bb5.
Now consider only the top 1 black response 3...Nf6. It is possible that black can draw with 3...a6, 3...d6, or 3...Bc5 as well, but if 3...Nf6 draws, then chess is solved.
Now consider the top 4 white moves: 4 O-O, 4 d3, 4 d4, 4 Qe2. If black draws against all 4, then it becomes trivial to prove that black can draw against all other white 4th moves as well. Say we continue with 4 O-O.
Now consider only the top 1 black response 4...Nxe4. It is possible that black can draw with 4...d6, 4...Bc5, or 4...Be7 as well, but if 4...Nxe4 draws, then chess is solved.
Now consider the top 3 white moves: 5 d4, 5 Re1, 5 Qe2. If black draws against all 3, then it becomes trivial to prove that black can draw against all other white 5th moves as well. Say we continue with 5 d4.
Now consider only the top 1 black response 5...Nd6. It is possible that black can draw with 5...a6 as well, but if 5...Nd6 draws, then chess is solved.
Now consider the top 4 white moves: 6 Bxc6, 6 dxe5, 6 Bg5, 6 Ba4. If it can be proved that black draws against all 4, then it becomes trivial to prove that black can draw against all other white 6th moves as well. Say we continue 6 Bxc6.
Now consider only the top 1 black response 6...dxc6. It is possible that black can draw with 6...bxc6 as well, but if we can prove 6...dxc6 draws, then chess is solved.
Now consider only the top 1 white move: 7 dxe5. If it can be proved that black draws against it, then it becomes trivial to prove that black can draw against all other white 7th moves as well. Say we continue with 7 dxe5.
Now consider only the top 1 black response 7...Nf5. It is possible that black can draw with 7...Ne4 as well, but if 7...Nf5 draws, then chess is solved.
Now consider only the top 2 white moves: 8 Qxd8+ and 8 Qe2. If black draws against these, then it becomes trivial to prove that black can draw against all other white 8th moves as well. Say we continue with 8 Qxd8+.
Now consider only the forced black response 8...Kxd8.

Now we have reached a 26 men starting position and the 'modern computer' takes over from the 'good assistant' in the same manner: top 4 white moves 9 Rd1+, 9 Nc3, 9 h3, 9 b3, then top 1 black move, top 4 white moves and so on until the 7 men endgame table base is reached to tell: draw or not.

What is the basis for labeling these moves the "top moves?"

As a b3 player I feel left out and sad. 

#1213
If black has a proven draw against the human and engine top moves 1 e4, 1 d4, 1 c4, 1 Nf3, then it becomes trivial to prove that black can draw against 1 b3 as well.
Once it is proven that black draws against 1 e4, 1 d4, 1 c4, and 1 Nf3, it will become clear that they are objectively equivalent. It is unlikely that 1 b3 were to lose for white, so 1 b3 then becomes objectively equivalent as well and more players may chose 1 b3.

First two numbers are not good. Who ever proposed 10¹²⁰ as the number of possible games? (Shannon didn't even though the basic rules when he came up with the figure included the 50 move and triple repetition rules.)

Total number of possible finite games under current basic rules is ℵ₀. Total number of "possible" infinite games under current basic rules is ב₁ (text editor now insists on suffix to the left).

#1215
No, thanks to either the 50 moves rule or the 3 fold repetition rule the number of games is finite.

Never say never.

The FIDE basic rules of chess have not included the 50 move rule or the 3 fold repetition rules since 2017. 

Even before that the draws had to be claimed, so the number of possible games was still infinite.

And even with the current competition rules which include mandatory termination under a 75 move rule and a 5 fold repetition rule thus making the number of possible games finite, the total number of possible games is vastly greater than 10¹²⁰.

Yes, draws have to be claimed on this site as well as OTB. A played a game this year in which I delayed claiming a draw beyond the 50 moves and only claimed it when checkmate was imminent. Chess: DerekDHarvey vs predadan79 - 326504024 - Chess.com 

Wrong about both.  See 9.2.1 and 9.3 in https://handbook.fide.com/chapter/E012018

A 5-time repetition rule and 75-move rule were added in addition to this.  Apparently they do not require a player to claim them, but can be invoked by the arbiter.

Wasn't the 75-move rule introduced because computers had taught us that KNRvKR were not drawn but did take more than 50 moves?

Didn't need computers. Various examples were already discovered around the start of, and during the first half of the 20th. century.

But a position being not drawn but taking more than 50 moves to mate doesn't exclude it from being possible under the 50 move rule. I don't believe computers have yet determined, for example, whether the 75 move rule would be sufficient to accomodate all two knights versus pawn mates, which can take up to 115 moves.

You don't think Black ever reaches a position in any line where the top engine move, for a given engine, wouldn't hold the draw, but another one would?  Engines lose to each other all the time.

So "top 1 move" is nonsense on its face, and if you have to even go to top 4 for both sides in most positions to be safe (and I wouldn't guarantee that is enough), it gets an awful lot less convenient for you.

Tell you what, instead of betting, since you've pre-weaseled-out of that, how about solving one subset of an ECO code to the 7-piece tablebases, like, say, one particularly forcing, but not trivially won/drawn, line of the Marshall Attack.  You know, as a proof of concept.  That's about the simplest case for you to deal with, and if you can do that with laptop Stockfish or an AWS instance or two, I'd find that a lot stronger evidence for your claims than anything you've said on this thread.

See a parallel forum for the likely way this question will be answered.