From a philosophical point of view, Leibniz's most interesting argument was that absolute space conflicted with what he called the principle of the identity of indiscernibles (PII). PII says that if two objects are indiscernible, then they are identical, i.e. they are really one and the same object. What does it mean to call two objects indiscernible? It means that no difference at all can be found between them--they have exactly the same attributes. So if PII is true, then any two genuinely distinct objects must differ in at least one of their attributes--otherwise they would be one, not two. PII is intuitively quite compelling. It certainly is not easy to find an example of two distinct objects that share all their attributes. Even two mass-produced factory goods will normally differ in innumerable ways, even if the differences cannot be detected with the naked eye.Leibniz asks us to imagine two different universes, both containing exactly the same objects. In Universe One, each object occupies a particular location in absolute space.In Universe Two, each object has been shifted to a different location in absolute space, two miles to the east (for example). There would be no way of telling these two universes apart. For we cannot observe the position of an object in absolute space, as Newton himself admitted. All we can observe are the positions of objects relative to each other, and these would remain unchanged--for all objects are shifted by the same amount. No observations or experiments could ever reveal whether we lived in universe One or Two.
Discovery first flew in 1984, the third orbiter to join the fleet. It was named for one of the ships commanded by Captain James Cook. Space shuttle Discovery is the most-flown orbiter; today will be its thirty-ninth and final launch. By the end of this mission, it will have flown a total of 365 days in space, making it the most well traveled spacecraft in history. Discovery was the first orbiter to carry a Russian cosmonaut and the first to visit the Russian space station Mir. On that flight, in 1995, Eileen Collins became the first woman to pilot an American spacecraft. Discovery flew twelve of the thirty-eight missions to assemble the International Space Station, and it was responsible for deploying the Hubble Space Telescope in 1990. This was perhaps the most far reaching accomplishment of the shuttle program, as Hubble has been called the most important telescope in history and one of the most significant scientific instruments ever invented. It has allowed astronomers to determine the age of the universe, postulate how galaxies form, and confirm the existence of dark energy, among many other discoveries. Astronomers and astrophysicists, when they are asked about the significance of Hubble, will simply say that it has rewritten the astronomy books. In the retirement process, Discovery will be the “vehicle of record,” being kept as intact as possible for future study.Discovery was the return-to-flight orbiter after the loss of Challenger and then again after the loss of Columbia. To me, this gives it a certain feeling of bravery and hope. ‘Don’t worry,’ Discovery seemed to tell us by gamely rolling her snow-white self out to the launchpad. 'Don’t worry, we can still dream of space. We can still leave the earth.’ And then she did.
Science can now help us to understand ourselves in this way by giving factual information about brain structure and function, and how the mind works. Then there is an art of self knowledge, which each person has to develop for himself. This art must lead one to be sensitive to how his basically false approach to life is always tending to generate conflict and confusion. The role of art here is therefore not to provide a symbolism, but rather to teach the artistic spirit of sensitive perception of the individual and particular phenomena of one's own psyche. This spirit is needed if one is to understand the relevance of general scientific knowledge to his own special problems, as well as to give effect to the scientific spirit of seeing the fact about one's self as it is, whether on elikes it or not, and thus helping to end conflict.Such an approach is not possible, however, unless one has the spirit that meets life wholly and totally. We still need the religious spirit, but today we no longer need the religious mythology, which is now introducing an irrelevant and confusing element into the whole question.Itwould seem, then, that in some ways the modern person must manage to create a total approach to life which accomplishes what was done in earlier days by science, art and religion, but in a new way that is appropriate to the modern conditions of life. An important part of such an action is to see what the relationshipbetween science and art now actually is, and to understand the direction in which this relationship might develop.