"That the vegetable creation should restore the air which is spoiled by the animal part of it, looks like a rational system, and seems to be of a piece with the rest. Thus fire purifies water all the world over. It purifies it by distillation, when it raises it in vapours, and lets it fall in rain; and farther still by filtration, when keeping it fluid, it suffers that rain to percolate the earth. We knew before that putrid animal substances were converted into sweet vegetables when mixed with the earth and applied as manure; and now, it seems, that the same putrid substances, mixed with the air, have a similar effect. The strong, thriving state of your mint, in putrid air, seems to show that the air is mended by taking something from it, and not by adding to it. I hope this will give some check to the rage of destroying trees that grow near houses, which has accompanied our late improvements in gardening, from an opinion of their being unwholesome. I am certain, from long observation, that there is nothing unhealthy in the air of woods; for we Americans have everywhere our country habitations in the midst of woods, and no people on earth enjoy better health or are more prolific."

“I am much obliged by the kind present you have made us of your edition of Vattel. It came to us in good season, when the circumstances of a rising state make it necessary frequently to consult The Law of Nations. Accordingly, that copy which I kept, (after depositing one in our own public library here, and sending the other to the college of Massachusetts Bay, as you directed,) has been continually in the hands of the members of our congress, now sitting, who are much pleased with your notes and preface, and have entertained a high and just esteem for their author.”

“[A] great Empire, like a great Cake, is most easily diminished at the Edges.”

“Can sweetening our tea, &c. with sugar, be a circumstance of such absolute necessity? Can the petty pleasure thence arising to the taste, compensate for so much misery produced among our fellow creatures, and such a constant butchery of the human species by this pestilential detestable traffic in the bodies and souls of men?—Pharisaical Britain! to pride thyself in setting free a single Slave that happens to land on thy coasts, while thy Merchants in all thy ports are encouraged by thy laws to continue a commerce whereby so many hundreds of thousands are dragged into a slavery that can scarce be said to end with their lives, since it is entailed on their posterity!”

“[Referring to private hospital funding alone:] That won't work, it will never be enough, good health care costs a lot of money, remembering 'the distant parts of this province' in which 'assistance cannot be procured, but at an expense that neither [the sick-poor] nor their townships can afford.' ... '[This] seems essential to the true spirit of Christianity, and should be extended to all in general, whether deserving or undeserving, as far as our power reaches.'”

“[T]he waters moved away from the North American Coast towards the coasts of Spain and Africa, whence they get again into the Power of the Trade Winds, and continue the Circulation. ...so long and so strong a Current as that of the Gulph Stream, thro' all the Latitudes of variable Winds, can only be accounted for, by its having a considerable Descent, and moving from Parts where the Water is higher, to Parts where it is lower.”

“How much more than is necessary do we spend in Sleep! forgetting that The sleeping Fox catches no Poultry,[Sept. 1743] and that there will be sleeping enough in the Grave,[Sept. 1741] as Poor Richard says.”