Mereological nihilism (also called compositional nihilism, or rarely simply nihilism) is the mereological position that objects with proper parts do not exist, and only basic building blocks without parts exist. Or, more succinctly, "nothing is a proper part of anything." The parts of the object can be both spatial and temporal; mereological nihilism also asserts that objects existing in time do not have any temporal parts.
Almost everyone knows what a part and a whole are; they are some of the first concepts that children or infants learn. A ball is made up of two halves, so the ball is a whole that is made up of two parts. Every single object we experience in the world outside of us and around us is a whole that has parts, and we never experience an object that does not have parts. For example, a tail is a part of a lion, a cloud is a part of a greater weather system or, in visual terms, the sky, and a nucleobase is a part of a DNA strand. The only things we know of that do not have parts are the smallest items known to exist, such as leptons and quarks, which can't be 'seen', so are not experienced—at least not directly, but indirectly through emergent properties. Thus all objects we experience have parts.
A number of philosophers have argued that objects that have parts do not exist. The basis of their argument consists in claiming that our senses give us only foggy information about reality and thus they cannot be trusted; and for example, we fail to see the smallest building blocks that make up anything, and these smallest building blocks are individual and separate items that do not ever unify or come together into being non-individual. Thus they never compose anything. So, according to the concept of mereological nihilism, if the building blocks of reality never compose any whole items, then all of reality does not involve any whole items, even though we may think it does.
Mereology (from the Greek μερος, ‘part’) is the theory of parthood relations: of the relations of part to whole and the relations of part to part within a whole. Its roots can be traced back to the early days of philosophy, beginning with the Presocratic atomists and continuing throughout the writings of Plato (especially the Parmenides and the Theaetetus), Aristotle (especially the Metaphysics, but also the Physics, the Topics, and De partibus animalium), and Boethius (especially In Ciceronis Topica).
As can be seen from Varzi’s passage, classical mereology depends on the idea that there are metaphysical relations that connect part(s) to whole. Mereological nihilists maintain that such relations between part and whole do not exist, since "wholes" themselves only exist at the subatomic level.
Nihilists typically claim that our senses give us the (false) impression that there are composite material objects, and then attempt to explain why nonetheless our thought and talk about such objects is 'close enough' to the truth to be innocuous and reasonable in most conversational contexts.
Partial vs. pure nihilism
There are a few other philosophers who argue for what could be considered a partial nihilism, or what has been called quasi-nihilism, which is the position that only objects of a certain kind have parts. One such position is organicism: the view that living beings exist, but there are no other objects with parts, and all other objects that we believe to be composite—chairs, planets, etc.—therefore do not exist. Rather, other than living beings, which are composites (objects that have parts), there are only true atoms, or basic building blocks (which they call simples). The organicists include Trenton Merricks and Peter van Inwagen.
Even though there are no tables or chairs, van Inwagen thinks that it is still permissible to assert sentences such as 'there are tables'. This is because such a sentence can be paraphrased as 'there are simples arranged tablewise'; it is appropriate to assert it when there are simples arranged a certain way. It is a common mistake to hold that van Inwagen's view is that tables are identical to simples arranged tablewise. This is not his view: van Inwagen would reject the claim that tables are identical to simples arranged tablewise because he rejects the claim that composition is identity. Nonetheless, he maintains that an ordinary speaker who asserts, for instance, "There are four chairs in that room" will speak truly if there are, indeed, simples in the room arranged in the appropriate way (so as to make up, in the ordinary view, four chairs). He claims that the statement and its paraphrase "describe the same fact". Van Inwagen suggests an analogy with the motion of the sun: an ordinary speaker who asserts that "the sun has moved behind the elms" will still speak truly, even though we accept the Copernican claim that this is not, strictly speaking, literally true. (For details, see his book "Material Beings".)
Philosophers in favor of something close to pure mereological nihilism are Peter Unger, Cian Dorr, and Ross Cameron.
- Buddhist atomism
- Elementary particles
- Mereological essentialism
- Metaphysical nihilism
- Peter van Inwagen
- Trenton Merricks
- Review of Trenton Merricks' book at the Wayback Machine (archived September 1, 2006)
- Review of van Inwagen's Material Beings