But in spite of this confirmation of that which needed none—in spite of the so-called corroboration of the “theory” by the so-called “ocular and physical proof”—in spite of the _character_ of this corroboration—the ideas which even really philosophical men cannot help imbibing of gravity—and, especially, the ideas of it which ordinary men get and contentedly maintain, are _seen_ to have been derived, for the most part, from a consideration of the principle as they find it developed—_merely in the planet upon which they stand_. Now, to what does so partial a consideration tend—to what species of error does it give rise? On the Earth we _see_ and _feel_, only that gravity impels all bodies towards the _centre_ of the Earth. No man in the common walks of life could be _made_ to see or to feel anything else—could be made to perceive that anything, anywhere, has a perpetual, gravitating tendency in any _other_ direction than to the centre of the Earth; yet (with an exception hereafter to be specified) it is a fact that every earthly thing (not to speak now of every heavenly thing) has a tendency not _only_ to the Earth’s centre but in every conceivable direction besides. Now, although the philosophic cannot be said to _err with_ the vulgar in this matter, they nevertheless permit themselves to be influenced, without knowing it, by the _sentiment_ of the vulgar idea. “Although the Pagan fables are not believed,” says Bryant, in his very erudite “Mythology,” “yet we forget ourselves continually and make inferences from them as from existing realities.” I mean to assert that the merely _sensitive perception_ of gravity as we experience it on Earth, beguiles mankind into the fancy of _concentralization_ or _especiality_ respecting it—has been continually biasing towards this fancy even the mightiest intellects—perpetually, although imperceptibly, leading them away from the real characteristics of the principle; thus preventing them, up to this date, from ever getting a glimpse of that vital truth which lies in a diametrically opposite direction—behind the principle’s _essential_ characteristics—those, _not_ of concentralization or especiality—but of _universality_ and _diffusion_. This “vital truth” is _Unity_ as the _source_ of the phænomenon. Let me now repeat the definition of gravity:—_Every atom, of every body, attracts every other atom, both of its own and of every other body_, with a force which varies inversely as the squares of the distances of the attracting and attracted atom.