Complex sentence: From the mid-twentieth century onward, critics distinguished Ishmael from Melville, establishing the character's mystic and speculative consciousness as a central force in contrast to Captain Ahab's monomaniacal force of will.
Split into simpler sentences: From the mid-twentieth century onward, critics distinguished Ishmael from Melville. They established Ishmael's mystic and speculative consciousness as a central force in the book in contrast to Captain Ahab's monomaniacal force of will.