Raymond Keene and Nathan Divinsky's book Warriors of the Mind attempts to establish a rating system claiming to compare directly the strength of players active in different eras, and so determine the strongest player of all time. Considering games played between sixty-four of the strongest players in history, they came up with the following top ten:
1. Kasparov
2. Karpov
3.Fischer
4. Botvinnik
5. Capablanca
6. Lasker
7. Korchnoi
8. Spassky
9. Smyslov
10. Petrosian
1. Kasparov
2. Karpov
3.Fischer
4. Botvinnik
5. Capablanca
6. Lasker
7. Korchnoi
8. Spassky
9. Smyslov
10. Petrosian