Sir, Your letter of the 15th is received, but Age has long since obliged me to withhold my mind from Speculations of the difficulty of those of your letter, that their are means of artificial buoyancy by which man may be supported in the Air, the Balloon has proved, and that means of directing it may be discovered is against no law of Nature and is therefore possible as in the case of Birds, but to do this by mechanical means alone in a medium so rare and unassisting as air must have the aid of some principal not yet generally known.
Thomas JeffersonAnd Botany I rank with the most valuable sciences, whether we consider its subjects as furnishing the principal subsistence of life to man and beast, delicious varieties for our tables, refreshments from our orchards, the adornments of our flower-borders, shade and perfume of our groves, materials for our buildings, or medicaments for our bodies.
Thomas JeffersonThe true fountains of evidence [are] the head and heart of every rational and honest man. It is there nature has written her moral laws, and where every man may read them for himself.
Thomas Jefferson