Another argument against cognitivism is the problems of Ryle's Regress or the homunculus fallacy. In the cortex, it is also referred to as the cortical homunculus. In the first anime series, the failed creation becomes the homunculus Sloth. This scientific model is known as the cortical homunculus. Indirect realism is argued to be problematical because of Ryle's regress and the homunculus argument. Haroun manages to destroy the homunculus as it attacks Sinbad. Firstly, while still only a homunculus, Tristram's implantation within his mother's uterus was disturbed. The result was the conception of the first sensory Homunculus. Upon his death, Bradley concludes that he had a good life despite being a homunculus. The motor homunculus is very similar to the sensory homunculus, but differs in several ways. He is killed by Bradley while trying to protect Lin from the homunculus. Some scientists speculated they saw a "little man" (homunculus) inside each sperm. She also grows close to Amoretta, a homunculus created by Chartruese from an angel's soul. Pea kills his fellow characters and turns them into a gigantic homunculus, which Briss fights. William Makepeace Thackeray wrote under the pen name of Homunculus.