Cartan's recognition as a first rate mathematician came to him only in his old age; before 1930 Poincaré and Weyl were probably the only prominent mathematicians who correctly assessed his uncommon powers and depth.
Cartan ng pagkilala bilang unang rate dalubbilang ang dumating sa kanya lamang sa kanyang gulang; bago 1930 Poincaré at Weyl ay marahil ang mga kilalang mathematicians lamang na tama ang tasahin ang kanyang kapangyarihan at hindi lalim.