In The Phenomenology of Spirit, the German philosopher Georg Wilhelm Friedrich (G. W. F.) Hegel delves into his ideas about sense-certainty and perception.

Let’s start with sense-certainty. As the term implies, sense-certainty involves senses and certainty. There’s an awareness of an object and a sureness that that object exists. For Hegel, sense-certainty is visceral. Hegel writes:

Our approach to the object must also be immediate or receptive, hence altering nothing in it as it presents itself and in grasping it refraining from comprehending it.

In a way, sense-certainty is rather basic. It doesn’t involve knowledge or comprehension. For example, sense-certainty of a computer would preclude pontificating about a computer and understanding why that computer is there and what it does. With sense-certainty, a rudimentary identification takes place, and nothing more.

Hegel talks about sense-certainty in an ephemeral manner. For Hegel, sense-certainty represents an “instance” in which someone becomes aware of “this”—“this" being the object or item in question. Thus sense-certainty is like a moment, or a collection of moments.

With perception, the scope widens substantially and the approach changes. When it comes to sense-certainty, the subject—the person—is passive: they are merely registering the “this” (the object). In the context of perception, the person is active. They are engaging with the object, thinking about it, using other experiences to further apprehend it.

In the realm of perception, the item doesn’t exist in a vacuum. Here, the item is thrust into a complex, interconnected web. The object is gauged in its relationship to other objects and things.

Indeed, for Hegel, it’s as if perception constitutes the level above sense-certainty. It’s the next step up.