Set theory and Foundations of Mathematics

1. First foundations of mathematics

Updates first apply to the below separate pages, then to the one page of all, then the PDF version (24 pages).
Some pages focus on model theory, others focus on set theory, others are philosophical
1.1. Introduction to the foundations of mathematics What is mathematics
Theories
Foundations and developments
Platonism vs Formalism
The cycle of foundations
1.2. Variables, sets, functions and operations Constants
Free and bound variables
Ranges and sets
Functions
Operations
1.3. Form of theories The variability of the model
Notions and objects
One-model theory
The diversity of logical frameworks
Examples of notions from various theories
Meta-objects
Components of theories
Set-theoretical interpretation
1.4. Structures of mathematical systems First-order structures
Structures of set theory
About of ZF set theory

Formalizing types and structures as objects of one-model theory
1.5. Expressions and definable structures Terms and formulas
The diverse kinds of symbols
Root and sub-expressions
Display conventions
Variable structures
Structures defined by expressions
Invariant structures
1.6. Logical connectives Tautologies
Negation
Conjunctions, disjunctions
Implication
Chains of implications and equivalences
1.7. Classes in set theory Classes, sets and meta-sets
Definiteness classes
Extended definiteness
1.8. Binders in set theory The syntax of binders
set-builder
Russell's Paradox
The function definer
Relations
1.9. Axioms and proofs
Statements
Realistic vs. axiomatic theories in mathematics and other sciences
Provability
Logical validity
Refutability and consistency
1.10. Quantifiers Bounded vs open quantifiers
Both main quantifiers ∃,∀
Inclusion between classes
Rules of proofs for quantifiers
Completeness of first-order logic
1.11. Second-order universal quantifiers Second-order quantification
Second-order Universal Introduction
Second-order Universal Elimination

Incompleteness of second-order logic
Axioms of equality
Defining new binders
1.A. Time in model theory The time order between interpretations of expressions
The infinite time between models
The metaphor of the usual time
The strength order of theories
Strengthening axioms of set theory
The main foundational theories
1.B. Truth undefinability Standard objects and quotes
Truth undefinability theorems
The hierarchy of formulas
Refined versions
Truth predicates
Properties of models
1.C. Introduction to incompleteness Existential classes
Provability predicates
The diversity of non-standard models
First incompleteness theorem
Second incompleteness theorem
Proving times
1.D. Set theory as a unified framework Structure definers in diverse theories
The unified framework of theories
Set theory as its own unified framework
Zeno's Paradox
2. Set theory
3. Algebra
4. Arithmetic
5. Second-order foundations

Other languages :
FR : Théorie des ensembles et fondement des mathématiques : Premiers fondements