The science of raja yoga proposes to put before humanity a practical and scientifically worked out method of reaching this truth. In the first place, every science must have its own method of investigation. If you want [knowledge of] chemistry, a certain method must be followed. You must go to a laboratory, take different substances, mix them up, compound them, experiment with them, and out of that will come a knowledge of chemistry….
I could preach to you thousands of sermons, but they would not make you religious until you practiced the method. These are the truths of the sages of all countries, of all ages, of men pure and unselfish, who had no motive but to do good to the world. They all declare that they have found some truth higher than what the senses can bring us, and they invite verification. They ask us to take up the method and practice honestly, and then, if we do not find this higher truth, we will have the right to say that there is no truth in the claim. But before we have done that, we are not rational in denying the truth of their assertions. So we must work faithfully, using the prescribed methods, and light will come.