Should I learn as many openings as possible or stick to one or two?

There was a time when I was obsessed with openings until I realized with advice from the more experienced players that chess is not more so about openings but rather tactics and strategies. So I stop making openings a priority. Wouldn't it be be ideal to thoroughly know one or two openings thoroughly or learn numerous openings? My mentor who is a 1900 player plays the same opening as white and black.

Looking over some of your games, openings arent your problem.  Its developing a game plan.  

It's true that the opening doesn't win the game. The purpose of the opening is to reach a playable middle game, hopefully with some kind of advantage. The advantage might only be your familiarity with the sorts of positions which arise in your chosen opening. So if you learn one opening thoroughly, then you will be able to focus more on tactics and other elements of the game. You might also save time on the clock if you are already familiar with the responses to a certain position or line.

A lot of book writers will mention in the introduction that they played a certain opening almost exclusively for several years. Some even say their knowledge of a specific opening was responsible for a title or tournament win.

Personally I believe a person will do better if they play an opening that feels good, and natural, and makes sense to them. Most likely you will become aware of openings which are related to your primary weapon and thereby build a repertoire, providing you with versatility.

Good luck

I think you should be able to play 6 openings relatively easy, two against e4, two against d5 and two as white. Think of the two openings for each as a back up, and to pice things up a bit. Opening theory is not too important.

"... Overall, I would advise most players to stick to a fairly limited range of openings, and not to worry about learning too much by heart. ... Just learn enough to get by, and spend more of your chess study time improving your tactical ability. ..." - FM Steve Giddins (2008)

Perhaps of interest:

https://www.chess.com/article/view/learning-an-opening-to-memorize-or-understand

I play only 1 opening with white and one with black and I'm an expert level player, and I don't consider openings to be a huge deal until master level. Until you're a FM or higher, it isn't needed and your time would be better spent on other things. 

If you play e4 learn everythig about this the same 1-d4 Now with black you need to know more options to defense

I know people who are probably around 1900 level and they tell me they don't know much about openings they just follow general opening principles and apply the tactical patterns that they know.  I'm not really that good so I can't really tell you when you should start studying openings. 

Neither, you should know all openings as well as possible. But if there are only two options, I pick the latter

Know the opening traps and pitfalls. A good defense is a good thing.

 "If you want to play chess competitively, then you must develop an opening repertoire." - GM Patrick Wolff (1997)

I play the Philidor/old Indian with black and London system with white. They can be played against anything. They're simple. Really, sub 2400 USCF ~2300 FIDE none of this matters. For us mortals, it's not needed to have an expansive opening knowledge.

 

I play the London as white too. I also don't think opening knowledge should be heavily emphasized outside of the opening principles and rather focus on the many other aspects of chess that will make up the lion's share of chess play and improvement in chess.

I think you should stick to one or two and really understand the plans and common themes that arise from the most common positions. If you play systems like the London, of course you don't have to study, because you won't make immediate threats. You make the standard 15-20 moves and just see what happens. While I understand that this is a perfectly reasonable approach to playing chess, some people prefer a more aggressive (and maybe more ambitious) approach and I think while you don't have to go crazy memorizing tons of sharp lines, you should be familiar with the basic plans and some traps. If you play e4 as a beginner, for example, and you are completely clueless about some strategic plans in, say, the French or the Caro, it's easy to float around aimlessly and commit positional blunders due to a lack of opening knowledge.

That is not true!

Even Mr London himself, the IM that plays it religously, will tell you that the London System is, simply put, bad against the Modern Defense.

 

1.d4 g6 2.Nf3 Bg7 3.Bf4? d6 4.e3 Nc6 (or 4...Nd7) 5.h3 e5! Advantage Black!

Against anything else, yes it is "playable", but don't expect much more than an equal game with it.

Oh, great, it's you. Indeed, many master level players our terrified of the modern defense and even don't recommend playing it, but if white plays correctly against it, there will be no advantage for black. Do you think you could beat Gata Kamsky when he's playing his london? Not only would you not get an advantage, or even equalize, you'd be wiped off the board. Stop being an ignorant troll. Also, in your line, there's no reason for white to play h3 yet, as black hasn't played Nf6 yet, and it's more of a waste of a move than anything else. You're deluded.

I've never met a London player who ever argued he plays the London to get an objective advantage- some will argue that being more familiar with the opening positions generally will give them a subjective advantage at times but most utilize the opening so they can mostly ignore the opening studies and focus on other areas of their chess (or even their black openings).

I'm pretty booked up on the london. I can play it for an advantage against anything, however slight. If the london were a simple opening used by club level players to avoid opening theory, then players such as Kamsky wouldn't play it. Some weak club players play the set-up with not much more knowledge than a few basic ideas, and for them, that'd be true, but for me, and for many others, especially stronger player, I know a lot more about the london than that and I'm deeply booked up on every major line. I deeply disagree with the notion that the london only gets white an even position. White's position is always easier to play, and he always holds a slight advantage, so long as he doesn't mess up the opening.

 

 

Well that's good for you! However I'd suspect you're being a bit generous on your views with the opening as if an objective advantage could be had with the London and/or easier to play in all positions then we'd see it in the mainstream GM play often instead of infrequently as we do. I think a less biased view of the opening is rather that white gets a comfortable position with chances for both sides without much effort and probably are easier to play for white often. The advantages White obtains from that opening are mostly seen in their familiarity with the positions and more likely accurate play in the resulting middle game positions. I believe it was Carlsen who said he played the London recently this year "just for a game" signalling he played it to avoid a battle of theory and just wanted a playable middle game with his opponent. I'm sure you have booked up on the London and may know the optimal moves for many lines which will give you an advantage against many. I'd be doubtful that it'd be proven to be objectively (best play) an advantage for White in all lines. What do you think is the most challenging response to the London? Do you play Bf4 on move two or three?

I play it on move 3 so if d4 Nf6 Nf3 c5 I can play d5. I'd say in a typical classical time control (say, 40 moves in 100 minutes, then 30 minutes, i/10) the Grunfeld bothers me the least, dutch also doesn't bother me at all, same with the slav. I'd say the queen's indian is one of the more annoying to try to play against, though the positions are quite comfortable, and I do think that the KID is the most objectively challenging line to face. It offers white more challenges than any other line. I do also feel that the London is creeping its way into mainstream GM play, as well.