COGITO, ERGO SUM ( I THINK, THEREFORE I EXIST )

You can challenge the existence of every thing, but your own existence cannot be doubted. Even when you deny your existence, you, the denier, exists. Descartes is said to have brought in this fundamental truth by saying, cogito, ergo sum- I think therefore I exist. But this truth existed even in ancient times. Asti Atma ( Self exists ), nastikya sadhana ( establishing denial ) asambhavat ( being impossible ) is the text of this in Sanskrit.
Adi Sankara finding the Self as the undeniable epistemological reality,made it also the basic ontological reality and claimed that the Individual Self (Atman ) is the same as the Universal Self(Brahman ).This is perhaps the greatest glorification of the human self found in the history of thought.

A VISION OF THE UNIVERSE

ASTRONOMICAL THEORIES AND THEIR VALIDATIONION

1.The Astronomical observations with the eyes and without much scientific traditions to support resulted in the Earth-centered theory of Astronomy in the West. In ancient civilizations they had better Sun- centered theories, unknown to the West. It was Galileo who made use of a telescope and improved the observation capability of Astronomers into space. His theory that all planets go round the Sun in circles was improved upon by Kepler, who found that the orbit of the planets was elliptical. Later Newton came with his theory of gravity which was proved to be correct in thousands of college laboratories all over the world. Then came Einstein who brought in the theory of relativity to explain the static model of a Universe. During the time of Einstein itself the Universe was found to be expanding and he had to review his idea of a static model of a universe. Now the 2011 Nobel Prize winning Scientists have come out with a theory that the Universe is expanding at an ever accelerating rate. Another challenge to Einstein's theory that the maximum velocity possible is that of the light is now coming up. During the period from Galileo to the 2011 scientists, the human capability to look into the depths of space has increased immensely. Space travel has also become part of human achievement. 2.But the question arises as to the scientific accuracy of Astronomical theories. The application of non-Euclidean geometry to outer space in Einstein's theory is an example. Out of the visible depth of space we have experiments and calculations in Astronomy. We do not know whether the current model of geometry is equally applicable to the most distant space. To give a basic example: The shortest distance between two points is a straight line for Newton; it is a curve for Einstein. In an ever expanding universe, it is a variable based on the velocity of expansion and another variable when the rate of expansion is accelerating.One can visualize the expansion as circular,elliptical or spiral and the force as centrifugal or centripetal. When the space is almost infinite and our observation into space is limited to a few light years, the theories are like the blind men's observations on the elephant. Even the observations are restricted by various factors such as conditions of light and visibility.Obviously we will not be able to observe the space behind a supernova. Thus there is use of imagination in addition to intellection in formulating theories in Astronomy. 3.In mythologies there is imagination of many worlds. Can we rule out that our experiential knowledge is limited to one universe now and that there are possibilities that we may have totally different systems elsewhere in space and time? The almost infinite nature of space and time will prevent us from acquiring complete knowledge of our " multiverse". This matter really need a discussion by experts.

A VISION OF THE UNIVERSE