“Why is it so difficult for us to think in relative terms? Well, for the good reason that human nature loves absoluteness, and erroneously considers it as a state of higher knowledge.”

“After some cogitation, it is difficult not to agree with Herman Bondi (1919 - 2005), who in his book 'Relativity and Common Sense' says:... The surprising thing, surely, is that molecules in a gas behave so much as billiard balls, not that electrons behave so little like billiard balls.”

“It is worth noting that a wrong folkoric definition of an Inertial Frame in the Popular Science literature (even in text books) reads that 'it is a frame in uniform motion'. We know very well by now that the idea of motion requires a frame of reference, so that such a definition of an Inertial Frame has no meaning whatsoever, confusing the reader because it tacitly reaffirms the idea of absolute motion -- when the goal of every didactic exposition of Relativity Theory should be precisely the opposite.”

“If Relativity Theory kills our deepest convictions, why not start by finding out why we believed in them for millennia?”

“To believe in nothing is as ridiculous as to believe in everything. Reason and factual evidence may convert a belief into knowledge.”

“One of the various theories proposed to explain the negative result of the famous Michelson-Morley experiment with light waves (conceived to measure the absolute space), was based on the ballistic hypothesis, i.e. on postulating that the speed of light predicted by Maxwell's equations was not given as relative to the medium but as relative to the transmitter (firearm). Had that been the case, the experiment negative results would have not caused such perplexity and frustration (as we shall see in forthcoming sections).”

“The notion of Local Inertial Frame is crucial to understanding Nature and, in particular, General Relativity. Notwithstanding, very few popular science books (not even textbooks) emphasize enough its fundamental character.”