The Philosophy of 'As if'

The Philosophy of 'As if' (hereafter As If ) is a 1911 book by the German philosopher Hans Vaihinger, based on his dissertation of 1877, which thereafter became his best known work. It was published in an English translation by C. K. Ogden in 1924.

Within a philosophical framework of epistemology, the book argues for false premises or false assumptions as a viable cognitive heuristic, in the realms of both science and religion. For example, simplified models used in the physical sciences are often formally false, but nevertheless close enough to the truth to furnish useful insight; this is understood as a form of idealization.