Essence refers to what a thing is. It asks what makes something the kind of thing it is. A tree is not a rock. A human is not a chair. A memory is not a fossil. Essence points to the claimed core nature and identity of a thing.
In traditional philosophy, essence is often contrasted with existence. Existence asks whether something is. Essence asks what something is. For many classical thinkers, essence represented things like souls. And many things were understood through their essence: their nature, form, and identity. Later existential thinkers challenged this, especially for human beings, arguing that we exist first and shape identity through life, choice, action, and meaning.
In TST Philosophy, essence is used carefully because it is on the ideas side of the split, but often attempts to describe a potential material-world thing. Essence is often a claim about what the core of a thing is, like the essence human souls. Or the life force of all living things. Human nature is also an essence claim. Whether someone believes their essence is an eternal soul, nature’s energy, the wholeness only formed during this life, TST does not automatically reject such claims, but does calibrate them.
This places essence inside the TST metaphysical split. In the material world, essence may refer to real features that make something what it is, but essence is not assumed without support. In the mind, essence is the idea of what we claim a thing is at its core. When an essence claim can be grounded in public evidence, it can move toward empirical understanding. When it goes beyond public evidence, TST identifies it as speculative and handles it with calibrated humility.
