3.1 Logical thinking

The classic example of logical thinking is a form of reasoning which goes like this: ‘If all cows are animals, and this is a cow, then it is an animal’. It starts with a generalisation, a premise which is assumed to be true and then deduces a conclusion about a particular case. There are three things worth noticing about this form of thinking. The first is that it attempts to be objective. The conclusion shouldn't depend at all on your particular point of view, your opinions and values about the world. The truth of the conclusion should be apparent to right-wing and left-wing politicians, freetraders and interventionists. The second is that it is necessary: that is, the conclusion always follows from the premise. You can't say ‘Well it all depends, sometimes the cow will be an animal and sometimes it won't.’ Finally, the structure of this thinking is sequential: it has the form ‘if a, then b’ – often called a chain of reasoning, and the chains are usually much longer than this one. As the word ‘chain’ suggests, logical thinking is a way of linking ideas or statements together.

This is a powerful and useful way of thinking, responsible for a good deal of the clarity we need to make sensible decisions. But we can't expect it to be good for everything. For example, logic isn't always a good way of sorting out emotional problems, such as who to marry or whether or not to have a child.