There are three aspects of knowledge: self-knowledge, the knowledge of another person, and the knowledge of the collectivity. Also, there are three ways of looking at the world: its past, its present, and its future. By yesterday is meant the past; by today is meant the present; and by tomorrow is meant the future. The knowledge of the past gives wisdom; the knowledge of the present gives power; the knowledge of the future gives peace. The one who is anxious to acquire knowledge must consider all these three aspects to be equally important.

For those who are treading the spiritual path it is as necessary to think of the world, especially at the present time, as it is to think of someone else and of themselves. No one should think that by position or rank, by profession or occupation, by condition or situation, he is too limited to think of the world; but each of us should realize that we are a self-sufficient particle of the whole. Each particle is responsible for the evolution of the world in proportion to the place it occupies in the cosmos; and everything a man naturally knows first about himself, and then about another, is of the greatest importance when he also begins to know something about the world at large. What he should know is what the world was, what the world is now, and what it will be in the future.

In the self-knowledge of past and present and future one has to learn

what was the origin of the soul,
how the soul has formed itself, how it has come to manifest, the knowledge of the process of manifestation
and the different stages through which it has passed towards manifestation.

Regarding the present one should learn

one's own condition,
the condition of one's spirit, of one's mind and body,
one's situation in life, and one's relationship to others;
one should also realize how far the soul reaches in the spiritual spheres.

And regarding the future, one should find the answers to the questions:

"Am I preparing for something that is to come, and what is there to come?
If life is a journey, what is the object of this journey?
What is the destination and how shall I reach it?
What preparations must I make for this journey and what must I carry to make the journey easy?
What are the difficulties that I may meet on my way?"

It is the understanding of these questions which is the knowledge of the future. And it is self-knowledge which helps man to know the past, the present, and the future of another. For those who know themselves another person is like an open book; they can read him clearly; his past is clear to them, and also his present and his future.

There are many ways in which people try to know about past, present, and future: by astrology, by palmistry, by physiognomy, by reading the features, and in many other ways. Although all such methods can often be helpful and give us some knowledge -- for knowledge is within our reach and we only have to ask for it and it is given -- yet by self-realization we can understand this knowledge so clearly at a certain stage, that no other method is necessary. It becomes natural; as it is natural for the eyes to see, so it becomes natural for the heart to see into the past, present, and future.

Looking into the past is just like looking deep down from great heights. It means probing the depths of life.
Looking into the present is just like observing a wide horizon, as wide as we can see.
Looking into the future is like looking upward to the zenith.

And the feeling we experience is different with each of these three ways of looking. One gives knowledge; the other gives power; and the third gives peace, as I said before. Knowledge is man's birthright and it is the sustenance of the soul. It is to gather knowledge that the soul has come on earth; the acquisition of knowledge is the only purpose the soul has in coming here.

In knowledge lies the satisfaction of the soul, the fulfillment of the purpose of life.