“Damien, I am an atheist but i have faith in gravity tho, but it isn’t exactly “faith.” – Challenger
 
My response, “no, I don’t agree, you don’t have faith in gravity or gravitation, as it is “a fundamental force” you have proof or if lacking some direct proof would use inference and if even less evidence you use conjecture, not faith. Do you gauntly thinking you need faith in gravity because you wonder or worry that when walking down a set of stairs that you going to fall back up? You don’t need faith (strong belief without evidence) as there is massive proof, almost to the point that it is easily self-evident. You don’t need faith (strong belief without evidence) for anything, as if its warranted it will or should have evidence or it doesn’t deserve not only strong belief but any amount of belief at all as sound beliefs need something to ground their worthiness in relation to reality; the only place evidence comes.
 
“Gravity, or gravitation, is a natural phenomenon by which all things with mass are brought toward (or gravitate toward) one another, including planets, stars and galaxies. Gravity is responsible for various phenomena observed on Earth and throughout the Universe; for example, it causes the Earth and the other planets to orbit the Sun, the Moon to orbit the Earth, the formation of tides, the formation and evolution of the Solar System, stars and galaxies. Since energy and mass are equivalent, all forms of energy, including light, also cause gravitation and are under the influence of it. On Earth, gravity gives weight to physical objects and causes the ocean tides. The gravitational attraction of the original gaseous matter present in the Universe caused it to begin coalescing, forming stars – and the stars to group together into galaxies – so gravity is responsible for many of the large-scale structures in the Universe.” Ref

Sound thinking to me, in a general way, is thinking, reasoning, or belief

that tends to make foresight a desire to be as accurate as one can

with valid and reliable reason and evidence.