Ghazzali's Alchemy of Happiness.
Know, however, that there is an immense distance and wide interval between perceiving the beauty of the Lord, and understanding that which constitutes its soul, marrow and essence. O seeker of the divine mysteries, those impotent astrologers and physicists, who, shut out from the knowledge of God, ascribe changes and events to the stars and to nature, resemble an ant, that seeing a pen making marks upon paper, should be overjoyed and cry out, "I have found out the secret of the effect. It is the pen that causes the marks." This class of men in another point resembles the natural man, who ascribes the influences in nature to heat and cold, water and earth: so a second ant looking on with attention, sees that the pen does not move of itself, but rather by the will of the hand: and he turns and says to the first ant, "You were mistaken; you did not perceive the real nature of the thing: you thought the marks and movements were caused by the pen. It is not so; the whole influence proceeds from the fingers and the pen is subject to the fingers." Beloved, this ant resembles the astrologer, who ascribes effects to the constellations. He does not know that he also is mistaken, and that the stars and the constellations are subject to the angels, and that the angels can do nothing without the command of God.
In the same manner as there is falsity, in the way in which the material world is regarded by the natural man and the astrologer, there is also a diversity of views among those who survey the spiritual world. There are some who, just as they are upon the point of entering upon the vision of the spiritual world, seeing that they discover nothing, descend back to their old sphere. There is also a difference of view between those who do succeed in reaching the spiritual or invisible world by meditation, for some have an immense amount of light veiled from them. Every