Actually the main aim of yoga as a science is to root out the cause of mental conflicts. It is these problems that act as blocks that prevent the influx of higher awareness, as well as happiness in life. It is during periods of perfect mental balance that one has his realizations, intuitive flashes and revelations, and lives in a state of increased awareness. These higher experiences don’t shine through when the mind is in a state of turmoil; and by turmoil we include the deeper levels of the subconscious mind. Many people feel relaxed on a conscious level and wonder why they don’t have higher experiences. The answer is simple – while they may consciously feel relaxed, the subconscious levels are certainly not relaxed. Also, one must be alert and awake. The whole system must be tuned to a high degree of sensitivity and receptivity. Most people when they feel relaxed become sleepy and drowsy. This is not the perfect condition under which the influx of higher awareness occurs.
To live in a continual state of higher awareness, one must always remain in a relaxed and receptive state. All the conscious and subconscious problems must be eradicated. So, you see, the removal of mental problems is an essential part of yoga. If yoga failed to clean out the mind, then it would fail to give the many benefits that it does, especially in higher spheres. Of course, one would still get some physical benefits from asanas etc., but these are an elementary though very fundamental and essential part of yogic life.
Yoga realizes that one must pass through the unhappiness associated with mental conflicts etc. before one can see the rainbow on the other side. This is beautifully summed up by a Zen quotation which goes as follows:
Under the sword raised high
Is hell making you tremble.
But walk on…
Arid there is the land of bliss.