Tetralemma

The tetralemma (catuskoti) is a figure that features prominently in Indian traditional logic. It states that with reference to any a logical proposition X, there are four possibilities:

: $X$ (affirmation): $eg\; X$ (negation): $X\; land\; eg\; X$ (both): $eg\; (X\; lor\; eg\; X)$ (neither)

It is found in the works of Nagarjuna, the founder of the Madhyamaka school of Mahayana Buddhism. Nagarjuna used the tetralemma to illustrate the seemingly contradictory nature of reality, where "conventional" reality suggests that entities are separate and have essence, and the "ultimate" reality of Mahayana Buddhism, that of shunyata, that all is lacking of self essence. The first verse of Nagarjuna's main work, the Mūlamadhyamakakārikā, states:

: "Neither from itself nor from another, nor from both, nor without a cause does anything whatever anywhere arise" (Garfield's translation)

Here X refers to any arbitrary "thing" in reality, and thus the following four logical propositions are rejected by Nagarjuna:

Things arise out of themselves: X

Things arise out of something else: not X

They arise out of both: Both X and not X

Without cause: Neither X nor not X

ee also

* Nagarjuna
* Paraconsistent logic
* Prasangika
* Two-truths doctrine

External links

*
* [http://www.thelogician.net/3b_buddhist_illogic/3b_chapter_01.htm Avi Sion (2002) "BUDDHIST ILLOGIC"]
* [http://twelvelinks.blogspot.com/2006/01/notes-on-tetralemma.html Twelve links blog "Notes on the tetralemma"]