- Extant(as used in biology and philosophy of biology)
- Still in existence; currently alive or present (the opposite of extinct).
- Lifespan of a taxon(as used in biology and philosophy of biology)
- The period of time during which a species or larger group exists, from when it first emerges until it goes extinct.
- Specimens(as used in biology and philosophy of biology)
- Individual examples or samples of something, especially individual organisms of a particular species.
- Taxon(as used in biology and philosophy of biology)
- A group of organisms classified together based on shared characteristics; it can be a species, genus, family, or any other level in the classification system.
- qualitative property(Chisholm's characterization in "On the Simplicity of the Soul" (1991))
- A property that characterizes substances (rather than other properties, states, or abstract objects), that could characterize a simple thing, and that is an internal or intrinsic property of anything it characterizes, such that a thing existing in isolation could have it.
- speciation(Discussed in relation to whether intrinsic properties arise and stabilize at the completion of speciation)
- The evolutionary process by which a new species is formed, after which the lineage segment defining the taxon is established
- species(Bacon's multiplicatio specierum theory adapted to epistemology by Crathorn)
- A representative likeness of an external thing, transmitted causally through a medium; in Crathorn's usage, a material mental quality in the mind that has the same nature as the external thing it represents.
- universal(Argument for the generality of Turing machines)
- A computing system capable of simulating any other computing system of the same or lesser power; used here to describe Turing machines as the most general model of computation.