thus became the "ideological center of the [New Wave] movement to rejuvenate conjectural literature". The term "New Wave" did not always meet with approval among those who were regarded as part of it (this included Moorcock, who denied that he was creating a movement). Brian Aldiss, for example, wrote to Judith Merril in 1966 that he suspected the term was "a journalistic invention of yours and Mike Moorcock's", and added "I feel I am no part of the New Wave; I was here before 'em, and by God I mean to be here after they've gone (still writing bloody science fiction)!" Merril was an important advocate for New Worlds and the New Wave, and popularized the latter in her anthology England Swings SF, which appeared in 1968; she spent almost a year in London, living near Moorcock, when researching the anthology in 1966–1967. Merril and writer Christopher Priest were among those who used the term "New Wave" to describe the work being done in New Worlds, but Aldiss was not the only writer to object to the term, and it never received a generally accepted definition. Critic Brian Attebery characterizes it as a "disruptive, existentially fraught and formally daring" style; Peter Nicholls hesitates to define it but comments that "perhaps the fundamental element was the belief that sf could and should be taken seriously as literature". In a 1967 interview, Ballard, one of the writers most closely associated with the New Wave, described modern US sf as extrovert and optimistic, and contrasted it with "the new science fiction, that other people apart from myself are now beginning to write", which he saw as "introverted, possibly pessimistic rather than optimistic, much less certain of its own territory." Whatever the exact definition of the term, between 1964 and 1966, New Worlds was at the forefront of the New Wave movement. Two guest editorials in 1962 and 1963 ("Which way to Inner Space?" by Ballard and "Play with Feeling" by Moorcock) were arguably the "first glimmerings" of New Wave ideas in sf magazines. Latham suggests that these were "the first volleys in the polemical offensive they would launch once [Moorcock] gained control of the magazine and installed [Ballard] as his resident visionary". The response to the New Wave from critics and sf fans was varied. Christopher Priest called New Worlds a "New Wave prozine", but lauded the talents of its writers and its