This innovative study offers stimulating discussions of the relation of conceptual expansion to truth, meaning, reference, ontology and paradox.This book studies the important issue of the possibility of conceptual change--a possibility traditionally denied by logicians - from the perspective of philosophy of mathematics. The author also looks at aspects of language, and his conclusions have implications for a theory of concepts, truth and thought. The book will appeal to readers in the philosophy of mathematics, logic, and the philosophy of mind and language.This book studies the important issue of the possibility of conceptual change--a possibility traditionally denied by logicians - from the perspective of philosophy of mathematics. The author also looks at aspects of language, and his conclusions have implications for a theory of concepts, truth and thought. The book will appeal to readers in the philosophy of mathematics, logic, and the philosophy of mind and language.This book studies the important issue of the possibility of conceptual change--a possibility traditionally denied by logicians--from the perspective of philosophy of mathematics. The author also looks at aspects of language, and his conclusions have implications for a theory of concepts, truth and thought. The book will appeal to readers in the philosophy of mathematics, logic, and the philosophy of mind and language.Preface; Acknowledgements; Introduction; 1. Historical background; 2. Frege's opposition; 3. The grammar of constraints; 4. Expansions as rational procedures; 5. Implications for concepts; 6. From words to objects; 7. G?del's argument; 8. Implications for thoughts; 9. 'I was led astray by language'; Epilogue. How do we go on from here?; References; Index. Ambitious and Innovative Review of Metaphysics