The Fourth dimension is what we experience when we astral project, communicate telepathically, or experience in an altered state.
When someone breaks a limb, the limb is placed in a cast.
When the cast is removed, the limb is withered, shriveled, and needs rehabilitation in order to retain its former range of movement and strength.
Meditation opens a part of our mind that has been defunct in most of the population.
Centuries of Christian control have made most of us unaware of the fourth dimension, as spiritual knowledge has been systematically removed and suppressed.
As humans, we can only see a small portion of the electromagnetic spectrum.
Insects can see ultraviolet light and more.
Many animals can sense things that a human cannot. Just because someone cannot see or hear something; that does not mean it doesn't exist, as with ultraviolet light, X-rays, gamma rays and other forms of energy.
When one opens one's mind, it can take time for one to adjust.