Probably because of their etymological basis in sophistry and the sophists, these words have not always been thought to suggest wholly admirable qualities: “complex,” yes, but perhaps “deviously, needlessly complex” was sometimes the implication. Today the meaning has generally elevated to “complex, elegant, polished” or (especially of persons) “experienced and worldly-wise,” an antonym of naive and innocent. When you find these words in older prose, however, be alert for the pejorative senses.
