That is essentially the finding of a study in Clackmannanshire schools, which found that giving 177 P6 pupils an hour of philosophy a week over 18 months improved their thinking and reasoning abilities by the equivalent of 6.5 IQ points. It also led to improvements in their social and emotional development.

But the significant finding by researchers Keith Topping, from Dundee University, and Steve Trickey, from Clackmannanshire’s psychological services, is that the gains were sustained at the end of S2, even although the 115 pupils they followed up had done no more work on “collaborative philosophical enquiries” in secondary.

Dr Trickey said this was unusual three-and-a-half years after the original work. “This finding is important in that it would suggest that the time children spend in exploring philosophical concepts through structured interactive classroom practices, such as ‘Thinking through Philosophy’, can be a good long-term investment for their future,” he said.

The development has been led by Paul Cleghorn, who is based at the Click Community Learning Centre in Alloa.

The main aim is to get children to think more deeply and respond to teachers’ open-ended questions. Thus, the children would be given a story or poem by the teacher and each would be asked to think about what it meant individually. They would discuss it in pairs before moving to a whole-class discussion.

Coalsnaughton Primary has set up a project for 10 and 11-year-olds to work with their parents and grandparents to explore different perspectives on community issues through philosophical enquiry.

Mr Cleghorn said: “The difficulty with learning to be a better thinker is that thinking is invisible. Through appropriate language and a dialogical approach, we are helping to make thinking ‘visible’, so enabling youngsters to be more aware of the processes.

“The start is at nursery stage, where the skills, language and dispositions of good thinking have their roots. We all use language to make sense of the world, to build concepts. If, beginning at nursery school, children are given the tools for better critical thinking, we are beginning to build for a more reasonable world.”

Dr Trickey believes the classroom enquiry methods used in the philosophy project lend themselves to the goals of A Curriculum for Excellence, which should have more space for such collaborative approaches. But he warned the development of open “communities of enquiry” required a shift in teaching practice for many teachers. The role of the teacher in supporting whole class enquiry emphasises the role of the teacher as “curious facilitator”

rather than “expert instructor”.