31. The proofs of his great topological theorems are intuitionism , which at the time made a stand against set theory. 32. The fundamental distinguishing characteristic of intuitionism is its interpretation of what it means for a mathematical statement to be true. 33. These include the program of intuitionism founded by constructive set theories such as IZF and the study of topos theory. 34. In intuitionism , the term " explicit construction " is not cleanly defined, and that has led to criticisms. 35. He became relatively isolated; the development of intuitionism at its source was taken up by his student Arend Heyting. 36. Intuitionistic logic was developed by Heyting to study Brouwer's program of intuitionism , in which Brouwer himself avoided formalization. 37. Formalized intuitionistic logic was originally developed by Arend Heyting to provide a formal basis for Brouwer's programme of intuitionism . 38. Moore's ethical intuitionism has been seen as opening the road for noncognitive views of morality, such as emotivism. 39. He specialised initially in logic, publishing books on " Intuitionism " and " Intuitionist logic ". 40. Griss was a student of L . E . J . Brouwer and formulated an intuitionism based on a hegelian idealism.
