Brian W. Aldiss said this quote
“ Wells is teaching us to think. Burroughs and his lesser imitators are teaching us not to think. Of course, Burroughs is teaching us to wonder. The sense of wonder is in essence a religious state, blanketing out criticism. Wells was always a critic, even in his most wondrous and romantic tales.And there, I believe, the two poles of modern fantasy stand defined. At one pole wait Wells and his honorable predecessors such as Swift; at the other, Burroughs and the commercial producers, such as Otis Adelbart Kline, and the weirdies, and horror merchants such as H.P. Lovecraft, and so all the way past Tolkien to today's non-stop fantasy worlders. Mary Shelley stands somewhere at the equator of this metaphor. ”