Deep limits

Abstract

Abstract Any talk of limits to science will alarm many people and comfort others. There are some who would equate the very idea of limits to scientific knowledge with a violation of our freedom of thought and action. Limits of cost are one thing, but absolute limits are surely something completely different. Show me one of those and I’ll jump over it, tunnel under it, or simply skirt round it. Yet, the more we try to grasp what science is, and how it relates to the activity of human minds, the more we are drawn towards the possibility that limits might be deeply rooted in the nature of things. They might even define the nature of things. Maybe this should not surprise us: science exists only because some things are impossible. Limits are slippery things. If we were to arrive at a definition of ‘science’ or of ‘knowledge’, then at once we would have circumscribed what we are going to consider as scientifically knowable. We have established a limit. We might worry that this dilemma afflicts any system of rules and regulations that we care to follow. In some sense it does. If you set up a system of rules of reasoning, then you are by definition placing limitations on what you will count as being true. It should come as no surprise that there are limits to what can be deduced or excluded by any system of rules. Keep only rabbits in your garden and you should not be surprised if rabbits, and only rabbits, result.