The main ideas of Buddhism are contained in the statements known as the Four Noble Truths and the Middle Way which the Buddha proclaimed in his first sermon at the Deer Park near Benares in the first year of his ministry.
The Four Noble Truths are :

1. The Noble Truth of Suffering: This Truth deals with all the problems of life as represented by birth, old age, disease and death, including sorrows and frustrations of every kind. Obviously, these things are unsatisfactory and people try their best to avoid them and to be free of them. However, not only these, but all conditioned things can be unsatisfactory as they are transient, conflicting and phenomenal, lacking an underlying enduring substance, and can cause sorrows and frustrations to anyone who ignorantly clings to them. For those who want to avoid and to be free from suffering, this Truth teaches that a right attitude, the attitude of knowledge and wisdom, must be maintained towards all things. One must learn to know things as they are. The unsatisfactory facts of life must be observed, located and comprehended. Beyond this, one has to proceed to other steps set forth in the other Truths.

In short the First Noble Truth treats of the problems and problematic situations which are to be observed, located and comprehended.

2. The Noble Truth of the Origin of Suffering: In this Truth, the Buddha examines and explains how suffering arises through various causes and conditions. This Second Truth includes the profound law of causes and effects called the Paticcasamuppada or the Dependent Origination, the practical part of which is the well-known law of Karma. In short, the Second Truth teaches that all kinds of suffering have their origins in craving or selfish desire rooted in ignorance. Not knowing things as they are or being ignorant of their true nature, people crave for and slavishly cling to things. Through this process, they develop three kinds of craving: craving for sensual pleasures, craving for existence and craving for self-annihilation. Through unsatisfied desire or through inadequate response, they experience sorrows and frustrations. Through the three kinds of craving, they also perform various evil actions with the body, speech and mind, which result in the suffering both of themselves and others and whereby other evils are caused to grow.

To put it simply, the Second Noble Truth deals with the examination and explanation of the origin of the problems by way of causality. It points out the causes of the problems which one has to destroy if the good life is to be experienced.

3. The Noble Truth of the Extinction of Suffering: This third Truth deals with the goal of Buddhist endeavour. It tells us that when ignorance is completely destroyed through true knowledge and when craving or selfish desire is eradicated and replaced by the right attitude of love and wisdom, Nirvana, the state of perfect peace, absence of defilements and freedom from suffering, will be realized. For those who have not com – pletely destroyed ignorance and craving, the more ignorance and craving are diminished the less suffering will become. The more their life is guided by love and wisdom, by knowledge and compassion, the more their life will become productive of happiness and welfare, both of themselves and others.

The third Noble Truth serves as a prediction, a hope and an urge for the striving of the followers.