A distinction can also be made between iterability and presupposition. Iterability makes reference to the "repeatability" of certain text that is composed of "traces", pieces of other texts that help constitute its meaning. Presupposition makes a reference to assumptions a text makes about its readers and its context. As philosopher William Irwin wrote, the term "has come to have almost as many meanings as users, from those faithful to Julia Kristeva's original vision to those who simply use it as a stylish way of talking about allusion and influence".