[Dates in brackets are conjectural]
1. Oldenburg to Spinoza 16/26 August 1661
2. Spinoza to Oldenburg [September 1661]
3. Oldenburg to Spinoza 27 September 1661
4. Spinoza to Oldenburg [October 1661]
5. Oldenburg to Spinoza 11/21 October 1661
6. Spinoza to Oldenburg [Early 1662]
7. Oldenburg to Spinoza [July 1662]
8. de Vries to Spinoza 24 February 1663
9. Spinoza to de Vries [February 1663]
10. Spinoza to de Vries [March 1663]
11. Oldenburg to Spinoza 3 April 1663
12. Spinoza to Meyer 20 April 1663
12A. Spinoza to Meyer 26 July 1663
13. Spinoza to Oldenburg 17/27 July 1663
14. Oldenburg to Spinoza 31 July 1663
15. Spinoza to Meyer 3 August 1663
16. Oldenburg to Spinoza 4 August 1663
17. Spinoza to Balling 20 July 1664
18. Blyenbergh to Spinoza 12 December 1664
19. Spinoza to Blyenbergh 5 January 1665
20. Blyenbergh to Spinoza 16 January 1665
21. Spinoza to Blyenbergh 28 January 1665
22. Blyenbergh to Spinoza 19 February 1665
23. Spinoza to Blyenbergh 13 March 1665
24. Blyenbergh to Spinoza 27 March [1665]
25. Oldenburg to Spinoza 28 April 1665
26. Spinoza to Oldenburg May 1665
27. Spinoza to Blyenbergh 3 June 1665
28. Spinoza to Bouwmeester June 1665
29. Oldenburg to Spinoza [September 1665]
30. Spinoza to Oldenburg [Autumn 1665]
30A. Spinoza to Oldenburg 7 October 1665
31. Oldenburg to Spinoza 12 October 1665
32. Spinoza to Oldenburg 20 November 1665
33. Oldenburg to Spinoza 8 December 1665
34. Spinoza to Hudde 7 January 1666
35. Spinoza to Hudde 10 April 1666
36. Spinoza to Hudde [June 1666]
37. Spinoza to Bouwmeester 10 June 1666
38. Spinoza to Van der Meer 1 October 1666
39. Spinoza to Jelles 3 March 1667
40. Spinoza to Jelles 25 March 1667
41. Spinoza to Jelles 5 September 1669
42. Velthuysen to Ostens 24 January 1671
43. Spinoza to Ostens [February 1671]
44. Spinoza to Jelles 17 February 1671
45. Leibniz to Spinoza 5 October 1671
46. Spinoza to Leibniz 9 November 1671
47. Fabritius to Spinoza 16 February 1673
48. Spinoza to Fabritius 30 March 1673
48A. Jelles to Spinoza [April 1673]
48B. Spinoza to Jelles [19 April 1673]
49. Spinoza to Graevius 14 December 1673
50. Spinoza to Jelles 2 June 1674
51. Boxel to Spinoza 14 September 1674
52. Spinoza to Boxel [September 1674]
53. Boxel to Spinoza 21 September 1674
54. Spinoza to Boxel [September 1674]
55. Boxel to Spinoza [September 1674]
56. Spinoza to Boxel [September 1674]
57. Tschirnhaus to Spinoza 8 October 1674
58. Spinoza to Schuller [October 1674]
59. Tschirnhaus to Spinoza 5 January 1675
60. Spinoza to Tschirnhaus [January 1675]
61. Oldenburg to Spinoza 8 June 1675
62. Oldenburg to Spinoza 22 July 1675
63. Schuller to Spinoza 25 July 1675
64. Spinoza to Schuller 29 July 1675
65. Tschirnhaus to Spinoza 12 August 1675
66. Spinoza to Tschirnhaus 18 August 1675
67. Burgh to Spinoza 3 September 1675
67A. Steno to Spinoza [September 1675]
68. Spinoza to Oldenburg [September 1675]
69. Spinoza to Velthuysen [Autumn 1675]
70. Schuller to Spinoza [14 November 1675]
71. Oldenburg to Spinoza 15 November 1675
72. Spinoza to Schuller 18 November 1675
73. Spinoza to Oldenburg [November or December 1675]
74. Oldenburg to Spinoza 16 December 1675
75. Spinoza to Oldenburg [December 1675]
76. Spinoza to Burgh [December 1675]
77. Oldenburg to Spinoza 14 January 1676
78. Spinoza to Oldenburg 7 February 1676
79. Oldenburg to Spinoza 11 February 1676
80. Tschirnhaus to Spinoza 2 May 1676
81. Spinoza to Tschirnhaus 5 May 1676
82. Tschirnhaus to Spinoza 23 June 1676