In a strict sense, Henry Fielding cannot be a pragmatist. Yet, in a functional sense, he may be said to be pragmatic. Pragmatism is an American originated philosophy of Charles Pierce and William James in the latter half of the 1800s (c. 1870-1900). Pragmatism claims that choices--arising out of belief or out of a search for equilibrium between belief and doubt--are acceptable if (1) they can be proved empirically or, barring the possibility of proof in some areas (like love), if (2) they work emotionally, psychologically and practically for the person making the choice.
Pragmatism was the philosophical answer between dualistic extremes of (1) rationalism (reasoning is paramount) and empiricism (all must be proven through the senses) on the one hand and of (2) idealism (all is a relative mental construct) and realism (universal truths exist outside the mind) on the other hand. As the great American pragmatist John Dewey put it, pragmatism is interested not in these dualities that have been the bedrock of philosophy since Greek philosophers but in the practical "problems of men [humans]."
This is why simplified expressions of pragmatism can state that (1) if, in science, something can be empirically proven, it may be accepted as true and that (2) if in ethics, morality, religion and daily problems, a choice can work without creating greater doubt and without creating disequilibrium, it can be accepted as a true choice.
Henry Fielding, born in 1707, wrote fiction between 1741 and 1751. This is more than a century before Pierce, James, and Dewey developed pragmatism. Therefore, strictly speaking, Fielding cannot possibly have been a pragmatist.
Yet, if Fielding made choices that contributed to his religious, moral, ethical and/or personal equilibrium or that worked for him in a way that he had psychological integrity and equilibrium, it might be accurately said that in a functional sense he acted in a pragmatic manner. This means he acted in a manner that foreshadowed the principles of the later philosophy of pragmatism before it was actually inaugurated as a philosophy.
In fact, Fielding made many pragmatic choices that made life situations--in which he met with disequilibrium--work toward a new equilibrium. The first was when his father could no longer pay for his college education. Fielding chose to become a writer and began as a playwright. Later, Parliament reacted against his satirical, lampooning plays and passed the Theatrical Licensing Act and forbid the performance of his plays. Fielding chose, after first turning to journalism, to publish a satire of Richardson's novel, Pamela, and thus began one of the most influential careers in English literature. When his wife Charlotte died, leaving him with several children to raise, Fielding chose to marry his housekeeper and former lady's maid to his first wife. It is safe to say that, though not a pragmatist (being 100 years too soon), Fielding acted in pragmatic ways to re-establish equilibrium.