Leibniz: there are things existing by their parts.
If such things are all that exist, then that by which they exist does not exist. Therefore, something exists without parts, and is the cause of what exists by parts.
a.) Considered as existing from its letters, it is m, a, and n, none of which are composed of letters
b.) Considered as word, it is as simple as it can be, not composed of simpler words.
c.) Considered as a species, it is composed of a genus, a difference, and the genera and differences contained by these.
Question: What about a man as quantified or extended? Quantity exists by its parts, but it cannot be resolved to some simplest extended part. The letter “M” does not admit some smallest brick out of which the whole is piled up. True, if we divide it into grams or millimeters or in some other quantifiable way there will be a final unit, but no one takes this as simply indivisible quantity. Quantity must be therefore be subtended by some non-quantified reality.
Granting that only the quantitative character of the physical world simply objective, this objectivity rests on some foundation that is non-extended. Let these non-extended reality or realities that subtend the objective, quantified world be called monads.