Swami Vivekananda in his book Raja Yoga discusses the nature of creation and beautifully describes the positive effects of love and the problem with hate. This is an excerpt from one of the chapters.
It seems the consensus of opinion of the great minds of the world, and it has been nearly demonstrated by researches into physical nature, that we are the outcome and manifestation of an absolute condition, back of our present relative condition, and are going forward, to return to that absolute. This being granted, the question is: Which is better, the absolute (from where we have come and we are going) or this state (the present state)? There are not wanting people who think that this manifested state is the highest state of man. Thinkers of great caliber are of the opinion that we are manifestations of undifferentiated being and the differentiated state is higher than the absolute. They imagine that in the absolute there cannot be any quality; that it must be insensate, dull, and lifeless; that only this life can be enjoyed, and, therefore, we must cling to it. First of all we want to inquire into other solutions of life.
The absurdity of going to heaven after death
There was an old solution that man after death remained the same; that all his good sides, minus his evil sides, remained for ever. Logically stated, this means that man’s goal is the world; this world carried a stage higher, and eliminated of its evils, is the state they call heaven. This theory, on the face of it, is absurd and puerile, because it cannot be. There cannot be good without evil, nor evil without good. To live in a world where it is all good and no evil is what Sanskrit logicians call a “dream in the air”. Another theory in modern times has been presented by several schools, that man’s destiny is to go on always improving, always struggling towards, but never reaching the goal. This statement, though apparently very nice, is also absurd, because there is no such thing as motion in a straight line.
Every motion is a circle
Every motion is in a circle. If you can take up a stone, and project it into space, and then live long enough, that stone, if it meets with no obstruction, will come back exactly to your hand. A straight line, infinitely projected, must end in a circle. Therefore, this idea that the destiny of man is progressing ever forward and forward, and never stopping, is absurd.
Hating is a bad idea
Although extraneous to the subject, I may remark that this idea explains the ethical theory that you must not hate, and must love. Because, just as in the case of electricity the modern theory is that the power leaves the dynamo and completes the circle back to the dynamo, so with hate and love; they must come back to the source. Therefore do not hate anybody, because that hatred which comes out from you, must, in the long run, come back to you. If you love, that love will come back to you, completing the circle. It is as certain as can be, that every bit of hatred that goes out of the heart of a man comes back to him in full force, nothing can stop it; similarly every impulse of love comes back to him.