Buddhist-Meditation-Systematic-and-Practical

While there are many classifications of sunyata, some
present it from too many aspects which may be
confusing to the neophyte while others give it under one
or two headings, useful only for the wise: this
classification of sunyata has neither too many nor too
few aspects and fits well into our scheme of the
three-yanas-in-one.
To explain this further: First, one investigates oneself
and cannot find there any abiding entity—one is void of
self in both body and mind. For the next meditation, one
looks into what is other than "myself." This refers to
other people, all of whom are seen after examination to
be devoid of self. One looks at people with whom one
has widely differing relationships and notices that
whether it is one's wife who is beloved or one's enemy
who is hated—all are sunyata in their nature.
Non-dharma voidness, upon which one next meditates,
includes many spiritual events occurring during
meditation, such as the appearance of a light or the
hearing of a voice. Even such insubstantial things as
these, together with time, direction and other
non-material dharmas—all these are found to be
sunyata.
Finally, the fourth meditation, on dharma-form, applies
to all the material dharmas—form, color, and so
on—these, too, are all void in their nature. Under these
four aspects every phenomenon has been included and,
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