Originally Answered: Which is the greatest civilization in the history of planet earth?
Has India contributed the most to the continuation of the human species on this planet? YES
Almost everything known to mankind in the area of science, maths, medicine, metaphysics and astronomy came out of India. for eg: Indians were the first to conduct surgeries & use anesthesia, Indians came up with the concept of zero and the number system, Indians invented algebra, trigonometry and other areas of mathematics, Indians invented Yoga and martial arts, (even though it is wrongly depicted in the west to be a Chinese invention! The Chinese themselves acknowledge that they learnt it from India!) Indians built the first university, invented the first school of medicine - ayurveda, discovered the art of navigation; The list goes on and on and on!! Indians have, by far, made the most inventions and discoveries! Here is a quote from Einstein.
"We owe a lot to the Indians, who taught us how to count, without which no worthwhile scientific discovery could have been made!"
In fact, on doing further research, I have found out that some of the Europe's greatest inventions and discoveries were actually made in India thousands of years before Europe ever existed! For example, gravity! Isaac Newton did NOT discover gravity, it was discovered at least 2000 years before the British empire existed by an Indian astronomer by the name of Brahmagupta! (I hope I got the spelling right)
"The motion of the stars calculated by the Hindus before some 4500 years vary not even a single minute from the tables of Cassine and Meyer (used in the 19-th century). The Indian tables give the same annual variation of the moon as the discovered by Tycho Brahe - a variation unknown to the school of Alexandria and also to the Arabs who followed the calculations of the school... The Hindu systems of astronomy are by far the oldest and that from which the Egyptians, Greek, Romans and - even the Jews derived from the Hindus their knowledge."
- Jean Sylvain Bailly (French astronomer)
Where can we look for sages like those whose systems of philosophy were prototypes of those of Greece: to whose works Plato, Thales and Pythagorus were disciples? Where do I find astronomers whose knowledge of planetary systems yet excites wonder in Europe as well as the architects and sculptors whose works claim our admiration, and the musicians who could make the mind oscillate from joy to sorrow, from tears to smile with the change of modes and varied intonation?
-Colonel James Todd (American pioneer)
It will no longer remain to be doubted that the priests of Egypt and the sages of Greece have drawn directly from the original well of India, that it is to the banks of the Ganges and the Indus that our hearts feel drawn as by some hidden urge.
-Friedrich Mejer (English statesman)
"I am convinced that everything has come down to us from the banks of the Ganges, - astronomy, astrology, metempsychosis,.. It is very important to note that some 2,500 years ago at the least Pythagoras went from Samos to the Ganges to learn geometry...But he would certainly not have undertaken such a strange journey had the reputation of the Brahmins' science not been long established in Europe..."
-Francois Marie Arouet Voltaire (French writer and philosopher)
Which civilization was the centre of human existence for the longest period of time?
DEFINITELY India! India is the world's largest, oldest, and oldest continuous civilization. India was also the wealthiest civilization on the planet for ALL of human history, (except for the 19th and 20th century, of course!)
"The multiplicity of the manifestations of the Indian genius as well as their fundamental unity gives India the right to figure on the first rank in the history of civilized nations. Her civilization, spontaneous and original, unrolls itself in a continuous time across at least thirty centuries, without interruption, without deviation."
-Sylvain Levi (French Orientalist)
Was it the one land that all men desired to see? YES!
"India is the one land that all men desire to see, and having seen once, by even a glimpse, would not give that glimpse for the shows of all the rest of the world combined."