why is ruy lopez considered the strongest

i don't understand why the ruy lopez is white's best choice against 1.e4 e5

black does not have to play a6 and b5.

he also has a lot of options that probably lead to equality.   i

don't understand why italian game is not equal to ruy lopez because they have similar pawn structure the Bishop on f1 goes to the same a2-f7 diagonal in both systems. 

kings gambit has a lot of sharp lines.  won't a black player have more problems in that if he does not know what is he is doing.

please explain.

Wow, really?? I did not know that.

What choices ?  I certainly dont think there is anything better than the Ruy after 1 e4  e5  

All three of your sugested alternatives also require 2...Nc6 so half of your post doesn't really make any sense.

World Champions and other world class ( 2700+) GMs certainly don't agree with you it seems as many are known for playing the Ruy but almost none play the other openings you mention on a regular basis .  I can name several world champions that relied heavily on the Ruy in their opening repertoire and cant think of any who relied heavily on the other openings you mention , care to enlighten me ?  

No, you said you believe that the Italian and the Scotch are as good as the Spanish and that the Ponziani might be too. All you said about the Vienna is that it is a good option, not that it rivals the others for the spot of "best". So you said three, one of which was a maybe. Not four.

I didn't ignore the Russian Defence at all. All I did was find vault with your logic. I ignored nothing.

I love this opening, as BLACK...

Nice dodge !  The fact is that , as usual , you dont know what you are talking about , as most B class players don't but at least most of them know they don't know much about chess .  Your problem is that you think you know as much as masters and even GMs , encouraged by your engine no doubt and the fact that you rarely play otb tournament chess so that you are missing your " attitude adjustments " that most class players get on a regular basis when they play against experts and masters . I play enough OTB chess to know that I shouldnt argue with my superiors ( GMs in particular ) as I have had enough beatings by them to understand that they know far more than I do about chess . Kasparov brought back the scotch opening for a spell and I doubt anyone played it better than him and yet he played the Ruy far more .  As for the Italian game , thats what I played as a class player but later switched to the Ruy and from personal experience I believe the Ruy is superior for white to the Italian . 

Ruy Lopez is considered the best white weapon on 1.e4 e5 because all the alternatives enables theorically speaking, black to equalize.

Other openings lead to forced lines where black found the way (or the ways) to equalize, more complicated in ruy lopez, because there are many options for white.

For instance, white can choose between big centre with c3-d4, or with "simple" d3 where its not so easy for black to find counter play.

Of course, top players sometimes change with Scotch, Italian, 4 knight, and others (i like Vienna with g3 personnally), but its more for a surprise value.

Ruy Lopez is the more complicated opening, many ways, demands deep knowledge and skill, u dont have this in king's gambit for example.

About Italian and Ruy Lopez, u are right, usually lead to same structure.

But the move order makes the whole difference, Bb5 putting pressure on e5, u dont have this with Bc4.

common its just style theres no better or worse just good and bad. both have their merits and both are played equally - in fact italian game was the major battle in Karpov - Korchnoi 1982......

You mean 81 ?  There were a few Italian games in that match but more Ruys and one petroff I believe ... Korchnoi always playing black in those . 

just bd3 or ba6 is no good. even be2, although passive has some ideas, and is played by the best i think

throughout my career i have been playing italian and have better results than with spanish. i know many friends who play italian: eg. GAVRIKOV, SHOMOEV, even i asked SHORT and he says Italian is better but people want to push further the bishop...... his words if you dont believe mine

81... 82... youre probably right. it doesnt matter

I remember korchnoi always black and it said something for the karpov team that to beat the "best defender of all time" (petrosian maybe also) you had to play the "best" white opening..... so italian. ruy lopez it was open variant so they thought they could get an advantage there.... in the closed games i remember the karpov team was worried. you can see their analysis in the kasparov matches when black wins some games.... 

it was all discussed

Its not about rating but chess understanding .  You don't seem to get that but I am not surprised . Its not what a GM plays once in a blue moon but about what they play most often and against their peers in critical games that indicates what they believe to be " best " .  Many GMs will play inferior stuff against weaker players just to get them out of " book " and make them play chess .... confident that their chess understanding is superior to their weaker opponents . If you played more OTB chess you would learn/understand these things . Your " superior intellect " doesnt seem to help you much where chess is concerned .  

if you are talking about me well then let me inform to you i play it more than "once in a blue moon"....... many times. i believe it to be better (style personally) than the spanish. my results proved it. 

and this was before they started avoiding berlins, way before

i played plenty otb chess long long ago..... maybe something changes but from my education it is only the fashion.......

When the titled players say that the Spanish is the most complex opening, they aren't just talking about tactics, they are also talking about strategies. Even +2800 rated players can be led astray and make strategic errors in the Spanish. It says a tremendous amount about the Spanish that until 2000, the Berlin was considered to be just great for White. It took a world champion at the height of his powers to demonstrate Black's defensive resources. And even now, 15 years later, that variation alone is one of the most popular for both sides.

The Spanish has been studied as long as the modern game of chess has been around, and it's still offering huge challenges. There is no other opening that compares to the Queen of Openings in terms of its longevity and strategic complexity. 

Every single world champion has played the Spanish, as white or Black, and most have played both sides in serious competition. Few other openings have such a pedigree, and none beginning with 1.e4.