Philosophy
Essences and Essential Properties
Quick fact
Aristotle argued that the essence of a thing is what makes it what it is, but not all necessary properties are essential. For example, being a mammal is necessary for being a tiger in the actual world, but many philosophers argue it is not essential—whereas having a tiger's genome might be.
Why this is interesting
You know a tiger without stripes is still a tiger, but a tiger without DNA would not be. Yet what exactly gives a thing its 'tigerness'?
Read the full explanation
Understanding Essences and Essential Properties
Imagine a golden key that opens a specific lock. The key's shape is essential—without it, it wouldn't open the lock. Its color is accidental—you could paint it blue, and it would still work. In philosophy, 'essence' refers to the set of properties that a thing must have to be the thing it is. Essential properties are those properties that constitute the thing's identity; if a thing lost them, it would cease to exist as that very thing. Accidental properties, by contrast, are features that can be changed without destroying the thing's identity. For example, a table could be made of wood or metal, but its being a table might require a flat surface and legs. The task is to determine which properties are truly essential, and this is not always obvious.
A deeper explanation
The most famous account of essence comes from Aristotle, who distinguished between the 'substance' of a thing and its accidents. For Aristotle, the essence is captured by a definition that tells us what the thing is—its 'whatness.' He also introduced the idea of 'real essence' versus 'nominal essence' (Locke): real essence is the underlying constitution that makes a thing what it is, while nominal essence is the set of observable features by which we identify it. In modern analytic philosophy, essences are often analyzed through modality: a property is essential to an object if it is necessary for that object's identity across possible worlds. This modal account, however, has been challenged by Kit Fine, who argued that some necessary properties (like 'being such that 2+2=4' for Socrates) are not essential to him. Fine proposed that essence is better understood as a primitive notion that grounds necessity, not the other way around. This debate reveals that the nature of essences is not settled; it intertwines with questions about identity, modality, and the structure of reality.