If any religion has the Four Noble Truths and the Eightfold Path, then it can be regarded as a proper religion.
It is a very difficult for a man to find out why there are so many different religions, and which religion is the true one. Followers of every religion are trying to show the superiority of their religion. Diversity has created some uniformity, but in matters of religion, men took upon each other with jealousy, hatred and disdain. The most respected religious practices in one religion are deemed ridiculous to others. To introduce their divine and peaceful messages some people have to resorted to weapons and wars. Have they polluted the good name of religion? It seems that certain religions are responsible for dividing instead of uniting mankind.
To find a true and proper religion, we must weigh with an unbiased mind what exactly is a false religion. False religion or philosophies include: materialism which denies survival after death; amoralism which denies good and evil; any religion which asserts that man is miraculously saved or doomed; theistic evolution which holds that everything is preordained and everyone is destined to attain eventual salvation through mere faith.
Buddhism is free from unsatisfactory and uncertain foundations. Buddhism is realistic and verifiable. Its Truths have been verified by the Buddha, verified by His disciples, and always remain open to be verified by anyone who wishes to do so. And today, the Teachings of the Buddha, are being verified by the most severe methods of scientific investigation.
The Buddha advises that any form of religion is proper if it contains the Four Noble Truths and the Noble Eightfold Path. This clearly shows that the Buddha did not want to form a particular religion. What He wanted was to reveal the Ultimate Truth of our life and the world. Although the Buddha expounded the Four Noble Truths and the Eightfold Noble Path, this method is not the property of Buddhists alone. This is universal Truth.
Most people find it necessary to put forth arguments to 'prove' the validity of the religion that they are following. Some claim that their religion is the oldest and therefore contains the truth. Others claim that their religion is the latest or newest and therefore contains the truth. Some claim that their religion has the most followers and therefore contains the truth. Yet none of these arguments are valid to establish the truth of a religion. One can judge the value of a religion by using only common sense and understanding.
Some religious traditions require man to be subservient to a greater power than himself, a power which controls his creation, his actions and his final deliverance. The Buddha did not accept such powers. Rather, He assigned to man that very power by asserting that each man is his own creator, responsible for his own salvation. That is why it is said that 'There is none so godless as the Buddha and yet none so godlike'. The religion of the Buddhists gives man a great sense of dignity; at the same time it also gives him great responsibility. A Buddhist cannot put the blame on an external power when evil befalls him. But he can face misfortune with equanimity because he knows that he has the power to extricate himself from all misery.
One of the reason why Buddhism appeals to intellectuals and those with a good education, is that the Buddha expressly discouraged His followers from accepting anything they heard(even if it came from Himself)without first testing its validity. The teachings of the Buddha have remained and survived precisely because many intellectuals have challenged every aspect of the teachings and have concluded that the Buddha had always spoken the undeniable Truth. While other religionists are trying to 'reassess' their founder's teachings in the light of modern knowledge about the Universe, the Buddha's teaching are being verified by scientists.