American painter, born and died in Philadelphia. He received his first education as an artist from the painter James Claypoole, who was his uncle. In 1764 he went to England, where he studied with Benjamin West and had some success as a portrait painter. His painting, "The American School," painted in 1765, is a group portrait of West and the young artists, including Pratt, who studied with him in London. It can be seen at the Metropolitan Museum of Art, New York. On his return to Philadelphia, Pratt found portrait painting did not give adequate financial returns; however he has left us some fine portraits.