Contiguity has been a central part of associationist analyses since the British Empiricists. In the experimental literature, the problem of figuring out the parameters needed for acquiring an association due to the contiguity of its relata has sometimes been termed the problem of the “Window of Association” (e.g., Gallistel and King 2009). Every associationist theory has to specify what temporal window two properties must instantiate in order for those properties to be associated.[32] A related problem for contiguity theorists is that if the domain generality of associative learning is desired, then the window needs to be homogenous across content domains. The late 1960s saw persuasive attacks on domain generality, as well as the necessity and sufficiency of the contiguity criterion in general.