“As with physical gravity, an understanding of the forces of social attraction support predictions, or at least the broad outlines of futuristic anticipation, since these forces of agglomeration and intensification manifestly shape the future.”

“Predictive social science does not exist. Indeed, it seems to me that it cannot ever exist, since the behaviour to be predicted reacts to and is partly shaped by the words used by the predictors.”

“Einstein showed us how to find all the possible universes that were consistent with the laws of physics and the character of gravity, how to reconstruct their pasts and predict their futures. But actually finding them was no easy task.”

“Two forces rule the universe: light and gravity.”

“Inflation takes advantage of this possibility… to let gravity be the repulsive force that drove the universe into the period of expansion that we call the Big Bang. In fact, when one combines general relativity with conventional ideas, now, in particle physics there really is a pretty clear indication, I should say, not quite a prediction… that at very high energy densities one expects to find states of matter which literally turn gravity on its head and cause gravity to become repulsive.”

“I have always held that social justice, even to the least the lowliest, is impossible of attainment by force.”

“Superficially at least the forces of electricity and magnetism seem to present the same kind of problem as gravitation. Experiment shows that two electrically charged bodies attract one another (or repel if their charges are of the same kind) with a force which conforms to the same mathematical law as the force of gravitation - both forces fall off inversely as the inverse square of the distance. The same is true of the magnetic force also; two magnetic poles attract or repel one another with a force which again follows the law of the inverse square of the distance.”

“The most constructive of the anarchists were, socially speaking, individualists, peaceful and harmless. The least constructive, socially speaking, were dedicated to the overthrow of force by counter force. But without exception, in the realm of economics every anarchist comes unglued.”

“Your brain is far too complex and mercurial for its behavior to be predicted in any but the broadest outlines or for any but the shortest distances in the future.”

“Our design, not respecting arts, but philosophy, and our subject, not manual, but natural powers, we consider chiefly those things which relate to gravity, levity, elastic force, the resistance of fluids, and the like forces, whether attractive or impulsive; and therefore we offer this work as mathematical principles of philosophy; for all the difficulty of philosophy seems to consist in this — from the phenomena of motions to investigate the forces of nature, and then from these forces to demonstrate the other phenomena…”