Assumptions

We should probe the space around us in exactly the same fashion as to study a surface, by following direct paths, making measurements, and recoding what we find, free from any preconceptions. What Einstein called a ‘thought experiment'; an experiment devised and carried out in our imagination. We can say a few word about the nature of thought experiments and their important role in understanding the physical world. A good example of the role of thought experiments is the 'law of inertia', first formulated by Galileo and later adopted by Newton as the first of the three famous ‘Newton’s laws’ of physics. Galileo had carefully observed and measured the motion of objects under various conditions, and finally concluded that the correct description was the exact opposite of the standard 'dogma' that had been accepted for almost two thousand years. That 'dogma', promulgated by Aristotle, stated that a force was needed to maintain motion, and when the force was removed. The motion stopped.

Galileo asserted that the motion would go on forever unless a 'force' was exerted to stop it. The Aristotelian belief was able to hold sway for so long for the simple reason that no actual experiment could be devised to verify Galileo’s assertion. There are always forces acting on an object: gravity, friction, and the force exerted by the earth on a falling object at the moment it hits, to name a few. Galileo had to imagine a situation in which all those forces were removed, and he concluded that under those circumstances an object would continue moving in the same direction at the same speed indefinitely. The importance of this thought experiment cannot be overstated, it allowed 'Newton' to put forces back into the picture in his second and third laws and to state the exact effect they would have on the motion of an object. As a result, the 'qualitative' description of the 'physical world' given by Aristotle was replaced by 'Newton’s precise quantitative' statements in the form of simple mathematical equations that became the basis of all of modern physics.




Uncovered

When ever John had need, therefore, of putting fear in the infidels' hearts, he should entertain the proposal for the council to effect the union of the churches. But since Manuel could see no hope of the Greeks ever finding spiritual peace and understanding with the Latins, John should never risk the parlous venture into actual union, for it would prove impossible and 'l fear lest an even worse schism may result - and then look! we have left ourselves uncovered to the infidels'.

At all events it was not prevailing spirit, and (as many a schoolboy knows or used to know) the union of the churches was in fact proclaimed, and with rare unanimity.


Setton, M. K., The Papacy and the Levant 11(1204 - 1571), The American Philosophical society, 1978, p. 58




The secret of the Hittites

The discovery of the Hittites has been an unusually stirring adventure of the human spirit. ln slightly more than a century a people of whom nothing but a name was known has become an integral part of the history of our civilization. Much still remains to be learned about the Empire of the Hittites, but a good beginning has been made.


Winston, Clara and Richard, (translators), The secret of the Hittites by Ceram, Publisher ex Libris, Harold and Eveline, 1955 OS66C35