1 e4 e5; 2 Nf3 Nc6; 3 Bb5

Forgive me any chess naivity but fairly new.  Am trying to understand openings more but come across problems that seem so familiar to oldies only get comment (if at all)  "better line is . . ." type of analysis rather than commentry on what is x move trying to achieve/why is it powerful.

Have come across above & can't really see why Bb5 is apparently a good move in the situation (Bishop seems just to get progressively driven back to a4 then c3).

Certainly it seems to get pieces out quickly; allow white early castle - but this could be achieved by Bishop move to other than b5.

Can anyone explain the thinking behind the move?

And while at it - know of any good books that concentrate on the thinking behind moves rather than just annotations of the type that better line is . . . without the why?

Would be appreciated.  Thanks.

The Bishop on b5 seeks to undermine Black's support of the e5 pawn by attacking the Knight.  The bishop doesn't really waste any tempi going to b3 because black is also wasting tempi to drive it back by making pawn moves, rather than bringing his pieces out.  This could result in either a queenside space advantage for black or weaknesses on the queenside depending on what other moves are made.

I also get frustrated by the sorts of comments you have found in books. One wants to know *why* a certain line is better. As you say, what is the thinking? The best book I have found that does this is Silman's Reassess your chess. It's brilliant. However, it is rather advanced. You might want to look at the The art of logical thinking by McDonald. I found this very useful. He goes through a number of Master games and explains - in my opinion - what the thinking is, what each player is trying to achieve. I like it a lot.

Now to your specific question about the Ruy Lopez. I used to play this years and years ago. Don't like it now so I may not be the best person to ask. There are players here who play this line virtually all of the time who may give a better answer.

After 1. e4 e5 2. Nf3 Nf6 3. Bb5 white has developed quickly and is ready to castle queenside. The bishop on b5 puts pressure on the black e5 pawn since 3. ... a6 4. Bxc6 bc: 5. Nxe5 seems to win a pawn. However, it doesn't win a pawn since black can easily get the pawn back with 5. ... Qd4 (or Qg5). However, if black doesn't do something about the bishop on b5 the threat to win the pawn on e5 will soon become real. This is why black often plays 3. ... a6 to force the bishop back. After 3. ... a6 4. Ba4 b5 Bb3 we should contrast the position with the Italian game. That is, compare the positions after these two sequences:

1. e4 e5 2. Nf3 Nf6 3. Bb5 a6 4. Ba4 b5 Bb3

1. e5 e5 2. Nf3 Nf6 3. Bc4

If I was white I think I prefer the first of these two positions. In both positions the white bishop on b3 or c4 is attacking the vulnerable f7 square. But there are two differences. Firstly, I would rather have my bishop on b3 than c4; on b3 it is safer (but just as effective because of its long range) and does not block the c pawn from advancing. Secondly, black has ben tempted to intoduce weaknesses in his queenside pawn formation that could prove decisive later on. For this reason, black does not normally play 4. ... b5 in the Ruy Lopez straight away but often forced to do it later as the pressure builds.

Of course, after 3. ... a6 white may not retreat, he may play the exchange variation 4. Bxc6; not with the intention of winning the e5 pawn straight away but with the aim of doubling the black pawns on the c file. Of course, there are positives and negatives in this exchange variation since black's bishop on c8 is activated along the c8-h3 diagonal by this move.

In short, the Ruy Lopez is a very strong opening for the attack-minded white player - there is no easy way for black to refute 3. Bb5 and black has to fight hard for equality. This is why I respond to 1. e4 with 1. ... e6 (French defence) :)

Also when the Bishop reaches b3 white's attack plays like the Italian opening (1. e4 e5 2.Nf3 Nf6 3.Bc4) except with the Bishop on b3 it is less vulnerable to a d5 counter so Black can't always rely on it. Since c4 and b5 are the best developments for the bishop you only have them to compare - Bb5 allows black to counter on the queenside with a6 and b5 while Bc4 risks a d5 counter. Choose which ever one you prefer.