Frege, Gottlob

"We must distinguish between use and mention."

"A function is unsaturated; it requires arguments."

"The sense of an expression determines its reference."

"Thoughts are neither physical nor psychological."

"Precision in thinking demands precision in language."

"Every rational being must accept the laws of logic."

"Objects and concepts are fundamentally different."

"The study of language illuminates the study of thought."

"Truth is the aim of all inquiry."

"Concepts are objective; ideas are subjective."

"Numbers exist in a realm of abstract objects."

"A name stands for an object; a concept stands for a function."

"Every complex thought is composed of simpler thoughts."

"We must overcome the prejudices of ordinary language."

"Logic is the science of thinking itself."

"Meaning is not arbitrary; it is determined by use."

"The pursuit of logical rigor is never misguided."

"Objects fall under concepts; concepts do not fall under concepts."

"A true proposition reflects the structure of reality."

"Understanding requires grasping the senses of expressions."

"Mathematics provides the model for all rigorous thinking."

"Thoughts are eternal truths, neither created nor destroyed."

"We apprehend thoughts; we do not create them."

"Logic cannot be other than it is."

"Every statement is a contribution to the growth of knowledge."

"The foundations of knowledge rest on logic alone."

"Ontology is the science of what is."

"We are all bound by the laws of thought."

"Numbers are the most abstract of all objects."

"Clarity is the sine qua non of philosophy."