In IQs, Cox-Buzan IQ is the mean IQ of the geniuses common to both the 1926 Catherine Cox genius list (300 geniuses) and the 1994 Tony Buzan genius list (100 geniuses). The following table shows the geniuses common to both the Cox and Buzan genius IQ lists, named as CB IQs in short. HCR stands for Hmolpedia citation ranking, which gives the modern corrective to the Cox-Buzan IQ, each adjusted up or down per HCR number, respectively:

 # Person $IQ_{CB} \,$ CR 1. Goethe (1749-1832) 213 347 Cox IQs (top 300 genius IQs) + Buzan IQs (top 100 genius) 2. Da Vinci (1452-1519) 200 43 3. Leibnitz (1646-1716) 194 62 4. Newton (1643-1727) 193 235 5. Galileo (1564-1642) 183 73 6. Mill (1806-1873) 183 28 7. Descartes (1596-1650) 178 58 8. Michelangelo (1475-1564) 178 9. Erasmus (1466-1537) 178 10 10. Milton (1608-1674) 177 11. Faraday (1791-1867) 175 44 12. Spinoza (1632-1677) 175 21 13. Copernicus (1473-1543) 173 41 14. Franklin (1706-1790) 173 15. Eliot (1819-1880) 173 12 16. Raphael (1483-1520) 170 17. Darwin (1809-1882) 169 218 18. Dickens (1812-1870) 165 19. Beethoven (1770-1827) 165 15 20. Bach (1685-1750) 165 21. Napoleon (1769-1821) 163 36 22. Mozart (1756-1791) 163 23. Lincoln (1809-1865) 160

The following is the list in text-copy format:

1. Goethe IQ 213
2. Da Vinci IQ 200
3. Leibnitz IQ 194
4. Newton IQ 193
5. Galileo IQ 183
6. Mill IQ 183
7. Descartes IQ 178
8. Michelangelo IQ 178
9. Erasmus IQ 178
10. Milton IQ 177
12. Spinoza IQ 175
13. Copernicus IQ 173
14. Franklin IQ 173
15. Eliot IQ 173
16. Raphael IQ 170
17. Darwin IQ 169
18. Dickens IQ 165
19. Beethoven IQ 165
20. Bach IQ 165
21. Napoleon IQ 163
22. Mozart IQ 163
23 Lincoln IQ 160

Discussion
A key benchmark on the IQ scale is the number 140, above which one is said to be in the genius level of intellect. The question immediately becomes: 'Who is the ceiling genius?' and 'What do the IQ values look like at the ceiling?' A solution to answering these two questions, noting that there are numbers far-fetched IQ estimates on the 200+ IQ page in the 200-400 range, is to average the independent estimated geniuses IQs of individuals reoccurring in the top 100 geniuses of all-time on both the Cox (1923) and the Buzan (1994) genius lists. This gives the above fifteen-point ceiling to affix to the top of the standard IQ scale, each of which can be considered as a representation of a hard-core 'anchor point genius':

These combined genius IQs give a excellent estimate to the top "ceiling IQ" on standard IQ scale as devised by Stanford psychologist Lewis Terman, in which IQ: idiot (below 20), imbecile (20-49), moron (50-69), deficient (70-80), dull (80-90), normal (90-110), smart (110-120), superior (120-140), genius (140 and over), top 100 all time genius (172 and over), ceiling genius (213) . [19] To be considered near the ceiling in IQ one would have to meet the following requirements, at a minimum:

(a) Have continuously produced genius work past the age of 60.
(b) Work must have two-century long "star quality"; i.e. still producing heat or brightness 200-years after publication.
(c) Have had an active vocabulary near the 100,000 word range.
(d) Have had a near mastery of all branched of knowledge, particularly the sciences.
(e) Have had pushed known knowledge into new uncharted territories.

As key rule here, then, according to the ceiling Cox-Buzan geniuses, to have had a legitimate IQ score in the 172 to 213 range, one would, at a minimum have been dead for at least 100-200 years, so as to allow for ‘generational judgment’ on the question of whether or not their accomplishments were truly genius and thus deserving of on of the world’s highest IQ scores.