We are all more or less proud of our past Indian civilization, but we actually do not know the real nature of that civilization. We cannot be proud of our past material civilization, which is now a thousand times greater than in days gone by. It is said that we are passing through the age of darkness, the Kali-yuga. What is this darkness? The darkness cannot be due to backwardness in material knowledge, because we now have more of it than formerly. If not we ourselves, our neighbors, at any rate, have plenty of it. Therefore, we must conclude that the darkness of the present age is not due to a lack of material advancement, but that we have lost the clue to our spiritual advancement, which is the prime necessity of human life and the criterion of the highest type of human civilization.
Throwing of bombs from airplanes is no advancement of civilization from the primitive, uncivilized practice of dropping big stones on the heads of enemies from the tops of hills. Improvement of the art of killing our neighbors by means of machine guns and poisonous gases is certainly no advancement from primitive barbarism, which prided itself on its art of killing by bows and arrows. Nor does the development of a sense of pampered selfishness prove anything more than intellectual animalism. True human civilization is very different from all these states, and therefore in the Katha Upanishad there is the emphatic call “Please wake up and try to understand the boon that you now have in this human form of life. The path of spiritual realization is very difficult; it is sharp like a razor’s edge. That is the opinion of learned transcendental scholars.”
Thus, while others were yet in the womb of historical oblivion, the sages of India had developed a different kind of civilization, which enabled them to know themselves. They had discovered that we are not at all material entities, but that we are all spiritual, permanent, and indestructible servants of the Absolute. But because we have, against our better judgment, chosen to completely identify ourselves with this present material existence, our sufferings have multiplied according to the inexorable law of birth and death, with its consequent diseases and anxieties. These sufferings cannot be really mitigated by any provision of material happiness, because matter and spirit are completely different elements. It is just as if you took an aquatic animal out of water and put it on the land, supplying all manner of happiness possible on land. The deadly sufferings of the animal are not capable of being relieved at all until it is taken out of its foreign environment. Spirit and matter are completely contradictory things. All of us are spiritual entities. We cannot have perfect happiness, which is our birthright, however much we may meddle with the affairs of mundane things. Perfect happiness can be ours only when we are restored to our natural state of spiritual existence. This is the distinctive message of our ancient Indian civilization, this is the message of the Gita, this is the message of the Vedas and the Puranas, and this is the message of all the real acaryas.
Ref: Chapter 2b, Science of Self Realization authored by Srila Prabhupada (Founder – Acharya, ISKCON)