Some Proposed Corrections to Maydole’s Temporal Contingency Argument
Robert Maydole presents an interesting argument for a supreme being, called the temporal contingency argument. The argument is a long deduction, and so is seen as somewhat difficult to comprehend. The version that I am critiquing appears in the Blackwell Companion to Natural Theology and appears as follows (with highlighted lines that I believe are problematic)[1]:
These errors are not fatal to the argument, however. Here is a quick workaround that I think preserves the spirit of Maydole’s deduction (using nested conditional proofs and the identity rule, for example). I’ve simplified some of the lexicon, but if pretty much follows Maydole’s definitions. A revised deduction is as follows:
1. P (premise)
2. M (premise)
3. (∀x)(Cx ⊃ Bx) (premise)
7. (∀x)(Tx ≡ ~Cx) (premise)
10. Cμ (8 UI)
11. Bμ (9,10 MP)
12. Bμ ⊃ Fμ (4 UI)
17 ~P (6,16 MP)
18. P & ~P (1,17 Conj)
19. ~(∀x)Cx (8–18 IP)
21. ~Cν (20 EI)
22. Tν ≡ ~Cν (7 UI)
23. (Tν ⊃ ~Cν) & (~Cν ⊃ Tν) (22 Equiv)
24. (~Cν ⊃ Tν) (23 Simp)
25. Tν (21,24 MP)
26. (∃x)Tx (25 EG)
27. (∀x)(∃y)Syx (premise)
33. ☐(∀x)(∀y)(Gxy ⊃ ~Gyx) (premise)
35. (∃y)Syν ⊃ (∃z)(Szν & Szz) (28 UI)
36. (∃z)(Szν & Szz) (34,35 MP)
37. Suν & Suu (36 EI)
40. Suν (37 Simp)
41. Tν & Suν (25,40 Conj)
42. ~Cu (39,41 MP)
43. Tu ≡ ~Cu (7 UI)
45. ~Cu ⊃ Tu (44 Simp)
46. Tu (42,45 MP)
47. Suu (37 Simp)
48. Tu & Suu (46,47 Conj)
49. (Tu & Suu) ⊃ Wu (30 UI)
50. Wu ⊃ ☐(∀z)(z≠u ⊃ Guz) (31 UI)
58. ☐~(∃y)Gyy (32 MN)
85. ~◊(∃z)Gzν & ~◊(∃z)(z≠ν & ~Gνz) (57,84 Conj)
86. Sν (85 def “S”)
87. (∃x)Sx (86 EG)
[1]R. Maydole. 2012. “The Ontological Argument”. The Blackwell Companion to Natural Theology. Ed. W.L. Craig & J.P. Moreland. Malden, MA: Blackwell Publishing. Document image retrieved from <http://commonsenseatheism.com/wp-content/uploads/2009/05/irrefutable.png>.
Posted on April 22, 2015, in Arguments for God and tagged modal logic, ontological argument, Robert Maydole, temporal contingency argument. Bookmark the permalink. Leave a comment.
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