claim: Floyd Mayweather Jr. is incapable of being a professional boxer.
evidence: The Novgorod Fourth Chronicle is a Russian chronicle of 15th century .. chronicle. chronicle. It is traditionally called `` Fourth '' according to the order of the modern publication of Novgorod chronicles , rather than chronologically .. Together with the Sofia First Chronicle , it is believed that it is derived from a common source .. Sofia First Chronicle. Sofia First Chronicle. Russian philologist Aleksey Shakhmatov tentatively called it the Novgorodsko-Sofiysky Svod -LRB- Novgorod-Sofia Corpus -RRB- and initially dated it by 1448 , but later revised his opinion to 1430s .. Aleksey Shakhmatov. Aleksey Shakhmatov. Novgorodsko-Sofiysky Svod. Novgorodsko-Sofiysky Svod. Some Russian philologists shared his opinion , while others attribute the common source to the 1418 Corpus of Photius , Metropolitan of Moscow .