Georgina Woodward
Your model of the world is wrong. We can now send spacecraft to Mars and do all sorts of other amazing things using our knowledge of how the world works at a fundamental level. Contrary to your model of the world, people ARE able to correctly see and know and represent the world: this is why we can have a thing called “science”.
Your model of the world is wrong. Contrary to your model of the world, living things, even very low-level living things, survive because they can correctly perceive and analyse the current situation in their surrounding world, and thereby find food and avoid danger.
So, contrary to what you say, the foundations of knowledge are secure. We do in fact know/ perceive/ experience the actual world. Furthermore, the brain can correctly analyse, interpret and collate the low-level knowledge, about the current situation in the surrounding world, acquired via the eyes, ears and nose etc.
It is only in the very high-level analysis, interpretation and collation of this knowledge by the brain, especially the high-level analysis, interpretation and collation of knowledge about high-level analysers-interpreters-collators of knowledge (i.e. knowledge about high-level beings, including human beings, including oneself), that misdiagnoses can occur.
Your model of the world is wrong because it flatly denies that the science that sends spacecraft to Mars is possible.