Yoga of Perfect Sight

Favourable Conditions

The vision of the human eye is modified in many ways when the conditions are unfavourable to good sight. Unfavourable conditions may prevail when the light is not agreeable to the patients. Some patients require a very bright light and others get along much better in a poor light. Many cases are hyper-sensitive to light and suffer from an intolerance to light which is called photophobia.

While intolerance to light may be manifest in most cases of diseases of the eyes, there are many cases in which the eyes are apparently healthy and in which photophobia may be extreme. (The cure for this condition is to have the patient sit in the sun with his eyes closed allowing the sun to shine on his closed eyelids as he moves his head from side to side.)

There are patients with good sight whose vision is materially improved when used in a bright light, as well as those with good sight whose vision improves when the eyes are used in a dim light. The patient should practise with the Snellen test card in a bright as well as in a dim light to accustom his eyes to all conditions.

The ability to perceive halos, or an increased whiteness, around letters or inside letters is a favourable condition. By using a card with a hole in it, it is possible for many patients to see an increased whiteness around a letter or inside the letter, which improves their vision of the letter. When a card with a hole is not used, one may be able to imagine a white halo around the inner or outer edge of the black part of the letter "O". When the card covers the black part of the letter "O", for instance, the white centre becomes of the same whiteness as the rest of the white page, which proves that it is the contrast between the black and the white which enables one to imagine the white halos.