 Intuitively, this principle says that no object can be even a partial cause of the very fact in virtue of which it exists; if it were, it would be a partial cause of its own existence. In the context of Kant’s theory of experience, it means that appearances cannot “reach back” and cause the very experiences in virtue of which they exist. From the 1780s until today, many have taken this problem to be fatal to Kant’s theory of  experience.[35]