When a person gazes at an object, he elevates it into his thought. If his thought is than attached to the supernatural Thought, he can elevate it to the supernal Thought. From there it can be elevated to the level of Nothingness, where the object itself becomes absolute nothingness. This person can then lower it once again to the level of Thought, which is somethingness.
At the end of all levels, he can transform it into gold.
Rabbi Dov Baer, The Maggid of Mezrich, (1704 – 1772)