We know the story of the thirsty crow and the pitcher. The crow felt very thirsty. The crow felt very thirsty. It felt the necessity of drinking water. It devised a means to satisfy its thirst. Its necessity impelled it to think how it could drink. At last it found out a way.
Thus the feeling of want is at the root of all discoveries and inventions in this world. Man feels the necessity of a thing. It urges him on to work to remove his want. This is at the root of the growth of human civilization. Primitive men felt they want of shelter, food, clothes, means of communication and protection from wild animals.
Their wants urged them to work. So they learnt how to build houses, make fire to cook food, make clothes of skin, weapons of stones etc. they learnt agriculture and produced food. But they were not satisfied with what they had. Man has got divine discontent.
This leads him to further discoveries and inventions. His knowledge increases. He feels not only physical but also intellectual wants. There is development of science and philosophy. A civilization progresses, man feels more want. New lands, new theories are thus discovered. New tools, instruments and machines are invented to satisfy his wants. If man had not this feeling of want, civilization could not have progressed so much.