Answer:
Chesterton explains how Thomas Aquinas was way ahead of his time in understanding what it means to be human and had a developed a great sense for ontology. He would argue that there are many of his own contemporaries that think and develop their ideas just like Aquinas did. Aquinas had started if not has paved the pathway and the theories of what is now known as anthropology. Aquinas also developed another section though not at his time considered different than Christianity, a newer form or a different type of religion. Aquinas did so much in his life that even now after hundreds of years later is still being taught. Standing against both time and current religious groups is truly an impressive feat, even some of the most well-known names have been forgotten due to these circumstances, and here Aquinas stands against all of that. This is why G. K. Chesterton claims, "St. Thomas Aquinas, perhaps more than he is anything else, is a great anthropologist." Step-by-step explanation:
I used Greanleafable's starting paragraph, hope this helps. this is a little over a 150 words. :)