“You can't measure time the way you measure the distance between two points.”

“You can't measure the mutual affection of two human beings by the number of words they exchange.”

“You can't control what you can't measure”

“Being with you and not being with you is the only way I have to measure time.”

“…by action on man all known force may be measured. Indeed, few men of science measured force in any other way. After once admitting that a straight line was the shortest distance between two points, no serious mathematician cared to deny anything that suited his convenience, and rejected no symbol, proved or unproveable, that helped him to accomplish work. The symbol was force, as a compass-needle or a triangle was force.”

“You said you're going far away," Tamaru said. "How far away are we talking about?"

"It's a distance that can't be measured."

"Like the distance that separates one person's heart from another's.”

“Clocks are inherently four-dimensional instruments, since the endpoints of their unit distances are events. Measuring rods, on the other hand, are three-dimensional measuring instruments; their end points are space points and they can be changed into four-dimensional measuring instruments only if events are produced at their end points according to a special rule.”

“Time can't be measured in days the way money is measured in pesos and centavos, because all pesos are equal, while every day, perhaps every hour, is different.”

“For the Lorentz transformation spatial measurements are also changed, because they are obtained relative to a moving system. In our example only time was transformed, while the distances between points at rest remained the same; the spatial coordinates, therefore, retain their identity.”

“The shortest distance between two points is often unbearable.”