Abstract
What is knowledge and what, if any, are its limits? In this essay I present a scientist’s view of our limits to knowledge, which come in many forms. Limits are set by our imagination and cultural backgrounds, by our technology, and by some of the laws of physics themselves. Science creates knowledge about the world through making models and measurement; and understanding the limits of our measurements is a central tenet of physics. Within physics, the calculation of these limits is generally harder than the measurements themselves, and within other disciplines it can be very difficult indeed. But measurements can only be made within the context of a model, and choosing between competing models can be very contentious. When competing models predict the same outcomes a further principle is required – Occam’s razor.