...and I think this is excellent advice.
It means that when you play someone weaker than you, you can assume he doesn't have all the skills you possess and you can try to go for some position you know isn't objectively best, but that will test him much more.
For example, you may play an objectively 'unsound' gambit against an inexperienced opponent and wouldn't risk it against someone of your strength.
Hmmm, maybe this is sound psychological advice, but unsound chess advice. (I'm not sure)
I play against pieces :|
@eseles
Well, it's not black or white 
It doesn't mean : play unsound against a weaker player and sound against a stronger player. It means you can take your opponent's weaknesses into account.
However, your approach is extremely good, if slightly more demanding. In OTB play, strong players have to find ways to save energy, and it sometimes requires to take shortcuts against some opponents.
@eseles
Well, it's not black or white
He he, i agree, that's why i said i'm not sure, to keep it somewhat ...purple! :D I also didn't say it can't work
It doesn't mean : play unsound against a weaker player and sound against a stronger player. It means you can take your opponent's weaknesses into account.
I think it's always good to exploit your opponent's weaknesses... but surely a low-rated player has more of them
However, your approach is extremely good, if slightly more demanding.
My approach? You mean that "I play against pieces"? Oh, it's just the title of a book written by the late GM Gligorich, which (title/quote) i find very nice! It's an objective approach, i guess.
In OTB play, strong players have to find ways to save energy, and it sometimes requires to take shortcuts against some opponents.
I see...
This discussion reminds me of the game i won against the highest rated player i've ever played! It's a long story to tell now, but i have to post it sometime :D
Hmmm, maybe this is sound psychological advice, but unsound chess advice. (I'm not sure)
I play against pieces :|
if you don't think human chess is heavily psychological (more so as the time control gets shorter) then you don't really understand chess. my opinion.
even if someone plays a "logical" "sound" move there still can be psychological aspects to it, however subtle.
He he, i agree with you about "human chess". But it's more a matter of understanding humans, than understanding chess, imo ;)
...and I think this is excellent advice.
It means that when you play someone weaker than you, you can assume he doesn't have all the skills you possess and you can try to go for some position you know isn't objectively best, but that will test him much more.
For example, you may play an objectively 'unsound' gambit against an inexperienced opponent and wouldn't risk it against someone of your strength.
Ahh, now THAT makes sense! I wonder if Hicetnunc had ever heard that phrase before? (play the board vs play the player)
Yes, it's pretty well known. There was a humorous English book authored by Simon Webb : 'Chess for Tigers'. The 2nd chapter title was : 'play the man, not the board'.
Lasker was one who would play the player and Fischer didnt respect Lasker much ( among the world champs ) due to this habit of his and Fischer referred to such a style of play as " coffeehouse " . Fischer played the board and once claimed he never played a move that he knew how to refute . I believe that the strongest players of today tend to play the board more ...
Always play the board. The information to find the strongest move is always available on the board, and that move will always be the best one. When you play the player, you compromise this for a weaker move based on your assumptions about what the player's proclivities might be.
A 2200 player recently said, 'If opponent is rated above you, play the board. If they are rated below you, play the player.'
What does 'play the player' mean? Can anyone please elaborate? Thanks.
I think the 2200 player has it the wrong way round.
Simon Webb, in Chess for Tigers, advocated the exact opposite.
Against a weaker opponent, keep it simple, stick to basics, and simply outplay him.
Against a stronger opponent, unbalance and complicate as much as you can. You will probably still lose, but you increase the randomness of the result.
Complicate to the point where neither of you understand what's going on.
You will probably make an error before he does, but just maybe he miscalculates the end of a forced line, or he falls into a hole before you do.
In my decades of playing chess, I have only ever beaten a titled player (FM) once OTB, OK, it was rapid time control, but still:
An example might lie in choice of opening.
The Colle has the reputation of being very drawish between players of equal ability but often allowing a strong player quickly to win against a markedly weaker opponent. So perhaps a strong player might choose to play it in a simul where he or she expects to be opposed mainly by weak opponents whereas he or she won't play it in a strong tournament.
Nothing unsound, but making allowance for the expected strength or weakness of the opposition.
When I was a player I never liked playing against the French Defense.
So in a big tournament I opened 1. c4 against a player known for the French Defense skills. he responded 1. ... f5 and I was happy.
If you know what a player plays you can avoid his lines or conversely try and refute one of his lines.
This could be considered playing the player.
perhaps you misunderstand. or are trying to be humorous.
if it's the former, by "human chess" I solely meant chess played between two humans with no computer engines involved. the main point being that it's impossible for psychology to be entirely extricated from a chess game played between two humans. it's always there, albeit less so at the professional level, more so at the amateur/enthusiast level. I would even go as far to say that a chess game (especially an internet blitz game) between two enthusiasts will be decided by which of two happens to be standing on the more solid mental ground at the time and nothing much else.
Oh, i understand you... And i agree with what you said above!
And i don't think what i said is difficult to understand, too ;)
I also like humour a lot, but i'm really talking seriously here :)
In the camp of the 2200 player quoted by the OP, you find GM Matthew Sadler, who advocates complicating against lower-rated opponents (and creating an asymetry of some kind - an 'imbalance' in Silman's language), and keeping it 'clean' agains this equals.
I guess opinions vary here.
Firebrand, I was joking with Mr. France, Hicetnunc, HE originally said the original quote to me in a phone conversation. Now I understand the saying, thanks to all the discussion.
I like what Ponz said too, about taking your opponent out of his comfort zone and throwing new stuff at him. And as always, Pfen gives great advice.
OMG Rooperi, what a game! Thanks for sharing it with us. Looks like something BF would have done!
All good stuff here in this thread. Thanks.
A 2200 player recently said, 'If opponent is rated above you, play the board. If they are rated below you, play the player.'
What does 'play the player' mean? Can anyone please elaborate? Thanks.