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  1. Per Lindström (2011). A Theorem on Partial Conservativity in Arithmetic. Journal of Symbolic Logic 76 (1):341 - 347.
    Improving on a result of Arana, we construct an effective family (φ r | r ∈ ℚ ⋂ [0, 1]) of Σ n -conservative Π n sentences, increasing in strength as r decreases, with the property that ¬φ p is Π n -conservative over PA + φ q whenever p < q. We also construct a family of Σ n sentences with properties as above except that the roles of Σ n and Π n are reversed. The latter result allows (...)
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  2. Per Lindström, First-Order Logic.
  3. Per Lindström & V. Yu Shavrukov (2008). The∀∃ Theory of Peano Σ1 Sentences. Journal of Mathematical Logic 8 (2):251-280.
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  4. Per Lindström & V. Yu Shavrukov (2008). The ∀∃ Theory of Peano Σ1sentences. Journal of Mathematical Logic 8 (02):251-280.
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  5. Per Lindström (2006). Note on Some Fixed Point Constructions in Provability Logic. Journal of Philosophical Logic 35 (3):225 - 230.
    We present a quite simple proof of the fixed point theorem for GL. We also use this proof to show that Sambin's algorithm yields a fixed point.
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  6. Per Lindstrom (2006). On Parikh Provability: An Exercise in Modal Logic. In Henrik Lagerlund, Sten Lindström & Rysiek Sliwinski (eds.), Modality Matters: Twenty-Five Essays in Honour of Krister Segerberg. Uppsala Philosophical Studies 53. 53--287.
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  7. Per Lindstrom (2006). Remarks on Penrose's New Argument. Journal of Philosophical Logic 35 (3):231-237.
    It is commonly agreed that the well-known Lucas-Penrose arguments and even Penrose's 'new argument' in [Penrose, R. (1994): Shadows of the Mind, Oxford University Press] are inconclusive. It is, perhaps, less clear exactly why at least the latter is inconclusive. This note continues the discussion in [Lindström, P. (2001): Penrose's new argument, J. Philos. Logic 30, 241-250; Shapiro, S.(2003): Mechanism, truth, and Penrose's new argument, J. Philos. Logic 32, 19-42] and elsewhere of this question.
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  8. Per Lindström (2004). Remarks on the Alleged Non-Determinateness of Certain Mathematical Concepts. In Christer Svennerlind (ed.), Ursus Philosophicus - Essays Dedicated to Björn Haglund on His Sixtieth Birthday. Philosophical Communications.
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  9. Per Lindström (2001). Penrose's New Argument. Journal of Philosophical Logic 30 (3):241-250.
    It has been argued, by Penrose and others, that Gödel's proof of his first incompleteness theorem shows that human mathematics cannot be captured by a formal system F: the Gödel sentence G(F) of F can be proved by a (human) mathematician but is not provable in F. To this argment it has been objected that the mathematician can prove G(F) only if (s)he can prove that F is consistent, which is unlikely if F is complicated. Penrose has invented a new (...)
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  10. Per Lindström (2000). Quasi-Realism in Mathematics. The Monist 83 (1):122-149.
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  11. Per Lindström (1997). Interpretability in Reflexive Theories - a Survey. Theoria 63 (3):182-209.
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  12. Per Lindström (1996). Provability Logic-a Short Introduction. Theoria 62 (1-2):19-61.
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  13. Per Lindström (1993). On ∑1 and ∏1 Sentences and Degrees of Interpretability. Annals of Pure and Applied Logic 61 (1-2):175-193.
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  14. Per Lindström (1993). On< I>∑< Sub> 1 and< I>∏< Sub> 1 Sentences and Degrees of Interpretability. Annals of Pure and Applied Logic 61 (1):175-193.
     
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  15. Per Lindström (1988). Partially Generic Formulas in Arithmetic. Notre Dame Journal of Formal Logic 29 (2):185-192.
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  16. Per Lindström (1984). On Certain Lattices of Degrees of Interpretability. Notre Dame Journal of Formal Logic 25 (2):127-140.
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  17. Per Lindström (1978). Omitting Uncountable Types and Extensions of Elementary Logic. Theoria 44 (3):152-156.
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  18. Per Lindström (1973). A Characterization of Elementary Logic. In. In Sören Halldén (ed.), Modality, Morality and Other Problems of Sense and Nonsense. Lund,Gleerup. 189--191.
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  19. Per Lindström (1969). On Extensions of Elementary Logic. Theoria 35 (1):1-11.
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  20. Per Lindström (1968). Remarks on Some Theorems of Keisler. Journal of Symbolic Logic 33 (4):571-576.
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  21. Per Lindstrom (1968). Remarks on Some Theorems of Keisler. Journal of Symbolic Logic 33 (4):571 - 576.
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  22. Per Lindström (1966). First Order Predicate Logic with Generalized Quantifiers. Theoria 32:186--195.
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  23. Per Lindström (1966). On Characterizability in Lω1ω. Theoria 32 (3):165-171.
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  24. Per Lindström (1966). On Relations Between Structures. Theoria 32 (3):172-185.
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  25. Per Lindström (1966). Some Results in the Theory of Models of First Order Languages. Göteborg.
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  26. Per Lindström (1964). On Model-Completeness. Theoria 30 (3):183-196.
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