The chain of human evolution started approximately 2.5 million years ago in Africa. With time a number of its species evolved. It terminated with the evolution of modern human -Homo Sapiens in East Africa around two lac years back.

Humans acquired linguistic ability seventy thousand ago. That was the point of the start of human history. The event is known as cognitive revolution. ; That enabled humans to learn and communicate.  With this acquisition humans went on spreading and dispersing in Europe and Asia out of its original habitat in East Africa.

Agricultural revolutionwas the next stage in the human history around 12,000 years ago. Man gave up nomadic way of life and permanent settlements began to be formed. Evolution of culture, religion and civilization unfolded.

 Now that man had acquired the ability to appreciate his relationship with surroundings and with other organisms he attempted to learn more and more. He has infinite curiosity. He has been learning about seas, mountains and sky. He attempted to learn himself. The information gathered over time accumulated in several traditions. These traditions are collectively known as religion.

Now he had a dependable guide for resolving his curiosities, problems and queries. He was assured that he has been blessed to have all the informations required for living by ancient sages in the religious texts and oral traditions

It was believed that we can obtain knowledge by proper study of these texts and traditions. Another source was listening to saints and other wise men. They believed that answers to al the mysteries of the universe are available in religious texts such as Vedas, Bible, Holy Quran etc. Answers to all the questions would be available in these texts or by contact with wise men. There is nothing new to be discovered.

It can be stated with responsibility that people did not believe in the modern concept of progress and development. They believed that golden period was in the past and the world is fixed. An event that did not occur in in the past, cannot take place in future.  Golden past can be brought back by sincerely following the wisdom of our sages and prophets. Human ingenuity can bring improvements in our day to day life. Overcoming the basic problems of living is beyond human capacity. Omnipotent Buddha, Confucius Jesus Christ and Mohammed were unsuccessful in preventing famine, disease, starvation,and war., How can we ordinary mortals even dream to do so?

Even though the past rulers and wealthy citizens alloted  funds and grants for education and health, the object was to preserve and organise the available resources rather than acquire new knowledge and technology. They did not have any pretension that they would invent new technology for treatment of diseases or develop new equipments and encourage economic growth.

A new tradition of knowledge appeared in the sixteenth century, which is known as Scientific inquiry. It has resulted in human population taking control of the biosphere. 

 Scientific revolution is the latest and decisive phase of human history. No human had circumnavigated the earth prior to 1522, when Magellan’s expedition returned to Spain after a journey of 72,000 kilometers.  It proved that the earth is not flat, it is round. The discovery challenged established wisdom.

The profound manuscriptof Copernicus “De revolutiomibus orbium coelestium (on the revolution of heavenly Spheres.” was released in 1543. It boldly declared that the sun, not the earth, was the centre of “heavenly spheres.”  The manuscript had clearly and unequivocally declared dissent with the traditional knowledge that The earth is the center of universe. These discoveries laid the foundation of the realisation that we do not know everything. It  was acknowledgement of Ignorance. New informations may prove our knowledge to be wrong. No concept, idea or theory can be sacrosanct and final. Dissent is the hallmark of science.

Rene Descartes pleaded for examining all the  established truths by application of scientific methods Scientific thought earned widespread recognition and respect  with the proposition of the theory of natural selection by Charles Darwin in 1859

Hallmark of science is implied in Science openly accepts collective ignorance about the most important subjects.  Science does not claim to have final answers to all the questions. Darwin never claimed that he is the final seal of the biologists.

Belief is the soul of religion, while dissent from the received wisdom is the hallmark of science. Science encourages doubts, religion crushes dissent.

Science rests on the acceptance of ignorance. It accepts that we do not know everything. More significantly science accepts  our present knowledge may be proved wrong as new informations accumulate. Science holds that there is no concept, idea, or theory that is sacrosanct and absolute; which cannot be challenged.

Science aims at gathering new knowledge besides according acceptance to ignorance. It applies mathematical tools to transform observations into comprehensive theories. Modern science is not limited to evolving theories. These theories are used for developing new technologies and acquiring new powers.