“The attempt of Lavoisier to reform chemical nomenclature is premature. One single experiment may destroy the whole filiation of his terms; and his string of sulphates, sulphites, and sulphures, may have served no end than to have retarded the progress of science by a jargon, from the confusion of which time will be requisite to extricate us.” 

“A little rebellion now and then is a good thing.”

“To take from one because it is thought that his own industry and that of his father’s has acquired too much, in order to spare to others, who, or whose fathers have not exercised equal industry and skill, is to violate arbitrarily the first principle of association--the guarantee to every one of a free exercise of his industry and the fruits acquired by it.”

“In matters of principal stand like a rock.”

“When the subject is strong, simplicity is the only way to treat it.” 

“I'm a greater believer in luck, and I find the harder I work the more I have of it”

“I believe that every human mind feels pleasure in doing good to another.”

“A wise and frugal Government, which shall restrain men from injuring one another, which shall leave them otherwise free to regulate their own pursuits of industry and improvement, and shall not take from the mouth of labor the bread it has earned. This is the sum of good government, and this is necessary to close the circlue of our felicities.”

“...as we advance in life these things fall off one by one , and I suspect we are left with only Homer and Virgil, perhaps with only Homer alone.”

“Reason and free inquiry are the only effectual agents against error.”

“It was one of the rules which above all others made Doctr. Franklin the most amiable of men in society, "never to contradict anybody.”

“I haven't failed. I've just found 10,000 ways that don't work.”

“Some men look at constitutions with sanctimonious reverence, and deem them like the ark of the covenant, too sacred to be touched. They ascribe to the men of the preceding age a wisdom more than human, and suppose what they did to be beyond amendment. I knew that age well; I belonged to it, and labored with it. It deserved well of its country. It was very like the present, but without the experience of the present; and forty years of experience in government is worth a century of book-reading; and this they would say themselves, were they to rise from the dead. I am certainly not an advocate for frequent and untried changes in laws and constitutions. I think moderate imperfections had better be borne with; because, when once known, we accommodate ourselves to them, and find practical means of correcting their ill effects. But I know also, that laws and institutions must go hand in hand with the progress of the human mind. As that becomes more developed, more enlightened, as new discoveries are made, new truths disclosed, and manners and opinions change with the change of circumstances, institutions must advance also, and keep pace with the times. We might as well require a man to wear still the coat which fitted him when a boy, as civilized society to remain ever under the regimen of their barbarous ancestors.” 

“I never submitted the whole system of my opinions to the creed of any party of men whatever in religion, in philosophy, in politics, or in anything else where I was capable of thinking for myself. Such an addiction is the last degradation of a free and moral agent. If I could not go to heaven but with a party, I would not go there at all.”

“القوة القانونية للحكومة يجب ان تتوقف على كبح الأفعال المؤذية للمواطنين تجاه الاخرين فقط . لا يوجد أذى لجارى ان قلت هناك أله واحد ، او هناك عشرين أله . هذا الفعل ليس سرقة لمحفظته او كسر لقدمه”