A Treatise of Human Nature

Imagine a world where everything you think is but a shadow of something you once felt or saw. Our mind’s perceptions are divided into two fundamental kinds: impressions, which are vivid and lively sensations, and ideas, which are their faint copies. These impressions are like the first brushstrokes on a canvas, bold and colorful, while ideas are the sketches made afterward, softer and less intense. When you close your eyes and think of your favorite place, the image you see is an idea, a gentle echo of the vivid impression you once experienced. This dance between impressions and ideas forms the very fabric of our consciousness.

Consider the taste of a ripe pineapple. Unless you have actually tasted it, you cannot form a true idea of its flavor. This shows us that simple ideas—those basic elements of thought—are always grounded in prior impressions. Every simple idea you hold in your mind has a corresponding impression that came before it. This is why a person born blind cannot imagine colors they have never seen, for the impression was never made on their senses.

Yet, the imagination is not a mere photocopier. It enjoys a remarkable freedom to rearrange, combine, and transform these simple ideas into complex ones. Like a painter mixing colors to create new shades, the mind can unite simple ideas into elaborate concepts, such as imagining a city that never existed or a mythical creature. However, these complex ideas still trace their roots back to the simple impressions that our senses first recorded.

Our memory plays a special role here. It preserves impressions more vividly than imagination, which tends to fade and alter ideas over time. When you remember a joyful moment, the memory brings it back with strength, but when you imagine a future event, the image is often dimmer and more fluid.

This fundamental principle—that ideas depend on impressions—forms the cornerstone of our understanding of human thought. It tells us that our knowledge is ultimately tied to experience, and that without sensory input, our minds would be barren landscapes.

As we move forward, we will explore how these ideas connect and associate, how we come to understand space and time, and how this empirical foundation shapes our grasp of knowledge itself. Let us now journey into the fascinating realm of how our ideas unite and form the complex tapestry of human thought.