Hume's Critique: Deconstructing Causality in Philosophy

Hume's Criticism of Causality

Criticism of the principle of causality is the cornerstone of Hume's philosophy. Rationalists considered causality a principle known clearly through reason. Descartes stated that the principle of causality allowed him to assert God's existence as the cause of the idea of infinity in his mind. Locke also used the principle of causality to accept the existence of external reality as the cause of our sensations and God's existence as the cause of the world and our own existence.

According to Hume, all arguments about matters of fact are based on cause and effect. Only through this relationship can we go beyond the evidence of our memory and senses. Furthermore, our notion of an ordered world would be impossible if we couldn't establish causal relationships between events, inferring future events from present impressions.

The Idea of Necessary Connections

Hume argued that the idea of causality implies a necessary connection between a cause and its effect. When the cause is present, we expect the effect to necessarily occur. For example, we expect a lead object to sink in water. We say that the cause, A, is placing the object on the water, and the effect, B, is the object sinking. However, a child accustomed to seeing dolls float in water might not imagine their new doll sinking. Similarly, the effects of gunpowder explosions or magnet attraction couldn't be known without experience.

No matter how much we observe something, we cannot know its effects without experience. The principle of causality, or the necessary connection between two ideas, cannot be known a priori, without experience.

The Role of Experience and Habit

Consider the difference between a child watching a doll sink in the bathtub and their mother observing the same event. Both have seen the same sequence of events and had the same experience. The experience of the same sequence repeatedly reveals something not initially noticed, affecting our minds: we develop a custom, a habit, of expecting heavy objects to sink in water. This leads to a circular argument where we attempt to prove what we assume as a starting point: the regularity of nature.