To question the external world is not to deny its importance. It is to examine how much weight our senses and habits of thought can bear. We wake each day expecting a physical world to greet us. Objects hold their shapes, events unfold in sequence, people remain where we last saw them. Yet all of this arrives through our senses, and senses can mislead. They show us mirages, shift colours in different light, and fill dreams with impossible scenes.

Doubt, once introduced, spreads quickly. If a single perception can deceive, what stops all of them from doing so? That thought can spiral into the idea that our experience might be a grand illusion, indistinguishable from reality. Even without such extremes, we can ask whether what we perceive is reality itself or only an image shaped by our minds.

Some treat this doubt as a challenge to be overcome. They point to the stability of experience and its usefulness in navigating life. If the world we encounter were entirely false, it would be hard to explain the regularity with which it supports our actions. Others argue that this regularity is exactly what makes belief in the world reasonable. It fits the evidence better than the idea that we are trapped in a perfect simulation.

Yet certainty is hard to secure. Even if the world exists as we think it does, our access to it is filtered. We see, hear, and touch only what our bodies allow. Instruments can extend those limits, but they still leave us within the boundaries of human perception.

The puzzle is that we cannot step outside our experience to check it against the world “as it really is.” We can only compare new experiences with old ones and look for patterns that hold. This may not satisfy a craving for absolute proof, but it gives us a practical foundation to live by.

In the end, belief in the external world is less about defeating every possible doubt than about recognising that doubt has limits. The same tools that raise suspicion—reason, observation, memory—also give us the best path back to trust.

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