In spite of the polar opposition between the two schools, they depend upon acommon premise. According to both sys- tems of philosophy, reflective thought, thinking that involves Inference and judgment, is not originative. It has its test in antecedent reality as that is disclosed in some non-reflective immediate knowledge. Its validity depends upon the possi- bility of checking its conclusions by identification with the terms of such prior immediate knowledge. The controversy between the schools is simply as to the organ and nature of previous direct knowledge. To both schools, reflection, thought involving inference, is reproductive jthe "proof" of its results is found in comparison with what is known without any infer- ence. In traditional empiricism the test is found in sensory im- pressions. For objective idealism, reflective inquiry is valid only as it reproduces the work previously effected by constitutive thought.