illustrated, than by the inclination of men to gain an acquaintance with the operations of nature; which disposition to enquire after the causes of things is so general, that all men of letters, I believe, find themselves influenced by it."[i-444] Through the sublimated mathematics of the _Principia_, Pemberton observed, "the similitude found in all parts of the universe makes it undoubted, that the whole is governed by one supreme being, to whom the original is owing of the frame of nature, which evidently is the effect of choice and design."[i-445] To what extent Franklin later gave evidence of his knowledge of Newtonian speculation we shall further discover in his _Articles of Belief_. He returned in the summer of 1726 on the _Berkshire_ to Philadelphia with Mr. Denham, a sweetly reasonable Quaker.[i-446] During this journey he wrote his _Journal of a Voyage from London to Philadelphia_, indicating a virtuoso's interest in all novel phenomena of nature. In Philadelphia he worked for Denham, then Keimer, and finally established his own printing house in 1728, a year after founding the Junto,[i-447] and the year of his _Articles of Belief_. By this time, Franklin, like Hume, wearied of metaphysics. Commonly this creed has been described as illustrating the deism of Lord Herbert of Cherbury. It is true that Franklin admits a God who ought to be worshipped, the chief parts of worship being the cultivation of virtue and piety; but there is no suggestion of Lord Herbert's fourth and fifth dogmas, that sin must be atoned for by repentance, and that punishment and rewards follow this life. His reaction against Calvinism may be shown in his failure to include reference to scripture, the experience of faith, and the triune godhead presided over by the redeemer Christ. As a deist he accepted "one supreme, most perfect Being." This Deity is the "Author and Father of the Gods themselves." "Infinite and incomprehensible," He has created many gods, each having "made for himself one glorious Sun, attended with a beautiful and admirable System of Planets." Franklin offered his adoration to that "Wise and Good God, who is the author and owner of our System." It is conventional to suggest that his interest in the plurality of worlds and gods should be traced to Plato's _Timaeus_.[i-448] In the absence of any conclusive evidence concerning Franklin's study of Plato, and in view of his profound awareness of contemporary scientific and philosophical thought, it seems more reasonable to see the source of this idea in the thought of his own age. Let us remember that with the growth of the heliocentric cosmology there resulted a vast expanse of the unknown, bound to intrigue the speculations of the philosophers of the age. We know that Ray, Fénelon, Blackmore, Huygens, Fontenelle, Shaftesbury, Locke, and Newton all wondered about the plurality of worlds and gods.