Species and Forms

Aristotle did not believe in Platonic Ideas. The forms do not have an independent existence outside of the individuals possessing those forms. But Aristotle was also not a nominalist; the forms do exist. We can talk about “dog” in general and utter sentences like: “The dog is an animal.” We don’t just observe a certain similarity between certain creatures and then choose to apply the word “dog” as a short-cut for these similarities. Dogs come in many different shapes and sizes and if we had just grouped animals together based on arbitrary likenesses, a German Shepard might as well be paired with a deer as with a Chiuaua. We do get a sense of what is essential about an individual in respect of its formal belonging.

Also,“form” is not mainly about reasonable categorization into an effective taxonomy, but rather refers to something inherent in every individual belonging to the species. Therefore the form of an individual is not actually dependent on anything existing in another individual or group of individuals. In fact, it is not even necessary for other items of the species to exist to be able to say that an individual belongs to that species. An animal species that is on the way to becoming extinct, will still exist when there is only a single member left. But even if all members were to disappear, the species would still exist as a historical fact and would thus still refer to something and therefore have existence. It could also exist as an inherent potential in something. Let’s imagine that all instances of a certain plant had gone extinct but one single seed still existed. The form of that plant would certainly exist whether or not that seed would ever get the chance to start growing. Or let’s imagine a seed that is a mutant; it represents a species that has never been and may never be unless that seed is allowed to grow, which is far from certain. Still that species already exists in that seed.

I have been talking about species and forms as if they were two distinct phenomena, and unfortunately that is also how they are treated by modern commentators of Aristotle. But we must remember that both “species” and “form” are translations of the same Greek word “eidos”. Since any concrete object is a combination of form and matter, there is necessarily form in everything, or knowing the correspondence of the terms we might as well say that there is a species in everything regardless of other instances of that species. The form of an object is whatever makes it what it is, which usually includes many things including what we usually identify as “species”. A part of the essence of Socrates is that he is human, belonging to the human species. Being human is in Socrates, and what is in something is not dependent on what is found outside of it. Socrates would be human even if he were the only human in the universe.