by Gerald E Sacks (Harvard University & Massachusetts Institute of Technology)

The author selects 23 of his papers in mathematical logic that pursue definability via priority, forcing, compactness and fine structure applied to classical recursion, hyperarithmetic sets, recursion in objects of finite type, measure, models and E-recursion. His general introduction provides a chronology both personal and technical.

• On the Degrees Less Than 0'
• Recursive Enumerability and the Jump Operator
• The Recursively Enumerable Degrees are Dense
• A Simple Set Which is Not Effectively Simple
• Metarecursive Sets (with G Kreisel)
• Post's Problem, Admissible Ordinals, and Regularity
• On a Theorem of Lachlan and Martin
• A Minimal Hyperdegree (with R O Gandy)
• Measure-Theoretic Uniformity in Recursion Theory and Set Theory
• Recursion in Objects of Finite Type
• Forcing with Perfect Closed Sets
• The α-Finite Injury Method (with S G Simpson)
• The 1-Section of a Type n Object
• Remarks Against Foundational Activity
• Countable Admissible Ordinals and Hyperdegrees
• The k-Section of a Type n Object
• Effective Bounds on Morley Rank
• Post's Problem, Absoluteness and Recursion in Finite Types
• On the Number of Countable Models
• Post's Problem in E-Recursion
• The Limits of E-Recursive Enumerability
• Inadmissible Forcing (with T A Slaman)
• Effective Forcing Versus Proper Forcing