Claudius Ptolemy's great contribution to astronomy was his famous work the Almagest, which presented formally the astronomical theories of the day that had evolved from the great debates within the different Greek philosophical schools. Claudius Ptolemy freely admitted that he had contributed little original research to the treatise but rather had based his conclusions principally on the work of Hipparchus. ...Ptolemy did not claim that his cosmological model described the actual conditions. It simply reproduced geometrically the observed motions of the known heavenly bodies and enabled their positions to be easily predicted for any particular time. ... Ironically, even when Copernicus' heliocentric theory had replaced the Ptolemaic system, many astronomers used Ptolemy's model to predict the motion of the planets, since its intricate calculations produced more accurate values.
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We do not inhabit a perfected world where natural selection ruthlessly scrutinizes all organic structures and then molds them for optimal utility. Organisms inherit a body form and a style of embryonic development; these impose constraints upon future change and adaptation. In many cases, evolutionary pathways reflect inherited patterns more than current environmental demands. These inheritances constrain, but they also provide opportunity. A potentially minor genetic change [...] entails a host of complex, nonadaptive consequences. [...] What "play” would evolution have if each structure were built for a restricted purpose and could be used for nothing else? How could humans learn to write if our brain had not evolved for hunting, social cohesion, or whatever, and could not transcend the adaptive boundaries of its original purpose?
Stephen Jay Gould
It may be observed of mathematicians that they only meddle with such things as are certain, passing by those that are doubtful and unknown. They profess not to know all things, neither do they affect to speak of all things. What they know to be true, and can make good by invincible arguments, that they publish and insert among their theorems. Of other things they are silent and pass no judgment at all, choosing rather to acknowledge their ignorance, than affirm anything rashly. They affirm nothing among their arguments or assertions which is not most manifestly known and examined with utmost rigour, rejecting all probable conjectures and little witticisms. They submit nothing to authority, indulge no affection, detest subterfuges of words, and declare their sentiments, as in a court of justice, without passion, without apology; knowing that their reasons, as Seneca testifies of them, are not brought to persuade, but to compel.
Isaac Barrow
Ancient scriptures tell us that man is more than the physical body. In fact, we have two bodies: the physical and the astral, or subtle. But we are the soul! According to the ancient Vedic scriptures of India, the size of the soul is 1/10,000 the tip of a strand of hair. It is located in the heart region and is the actual life force. The physical, as well as the astral or subtle body, acts as a covering or costume that the soul wears in its journey throughout the material sphere. As we pass from costume to costume or from body to body through the process known as reincarnation, the impressions of previous lives imprint themselves on the subtle body and are carried with us during each lifetime. In the dream state, activity in the subtle body becomes more dominant than activity in the physical body. Our dream experiences are often impressions accumulated from many lifetimes.
Bhakti Tirtha Swami
Third Theory.-According to this theory, there is nothing in the whole Universe... that is due to chance; everything is the result of will, intention, and rule. It is a matter of course that he who rules must know. The Mohametan Ashariyah adhere to this theory, notwithstanding evident absurdities implied in it. ...The Ashariyah were therefore compelled to assume that motion and rest of living beings are predestined, and that it is not in the power of a man to do a certain thing or to leave it undone. ...It follows also from this theory, that precepts are perfectly useless, since the people to whom any law is given... can neither do what they are commanded nor abstain from what they are forbidden. ...According to this theory, it must also be assumed that the actions of God have no final cause. All these absurdities are admitted by the Ashariyah for the purpose of saving this theory.
Maimonides
It is quite easy to include a weight for empty space in the equations of gravity. Einstein did so in 1917, introducing what came to be known as the cosmological constant into his equations. His motivation was to construct a static model of the universe. To achieve this, he had to introduce a negative mass density for empty space, which just canceled the average positive density due to matter. With zero total density, gravitational forces can be in static equilibrium. Hubble's subsequent discovery of the expansion of the universe, of course, made Einstein's static model universe obsolete. ...The fact is that to this day we do not understand in a deep way why the vacuum doesn't weigh, or (to say the same thing in another way) why the cosmological constant vanishes, or (to say it in yet another way) why Einstein's greatest blunder was a mistake.
Frank Wilczek
