SINGAPORE - Walking into Mr Richard Lim's office, the first thing you would notice is the pile of books on his table and more on the shelves.

The 59-year-old principal of Si Ling Primary School has collected hundreds of books over nearly 40 years as an educator, a testament to his life philosophy that there are always new things to learn.

He reads a variety of non-fiction titles on topics such as politics, business and the environment.

He is also proof that the breadth of one's reading is not linked to one's formal education status.

Mr Lim, an experienced school leader for more than 20 years, does not have a degree.

In fact, he quit the part-time Open University Degree Programme, nearly two decades ago, after completing just one out of the required six years.

Non-graduate teachers who had taken this course would have been placed on the graduate salary scale after obtaining a degree and earned higher pay immediately, he said.

But he felt it took too much time away from other commitments, like school, family and church. "I had to make a decision, and something had to go," said the father of two.

He did not feel that he was at a disadvantage. "I felt I could learn and read on my own… If your focus is right, you will have satisfaction, and you will be recognised."

The increments and promotions came, and after nine years of teaching science and mathematics in a secondary school, he was selected to go for a diploma in education administration - a year-long course at the National Institute of Education (NIE) - in 1989 to be trained as a school leader.

After the course, he was posted to Northland Primary School as vice-principal.

In 1994, he became principal of Xinghua Primary School, where he spent 3½ years.

He later spent seven years and nine years as principal of Henry Park Primary School and Anglo-Chinese School (Primary) respectively, before coming to Si Ling Primary at the end of 2013.

"You must not feel any lesser if you don't have a degree. Don't feel inferior," said Mr Lim, who has a certificate of education from the Institute of Education, which came before NIE.

"University gives a person that discipline and intense learning experience," he said. His 29-year-old daughter read mass communications at a local university and his 25-year-old son, who has a psychology degree, is studying for a master's degree in Biblical studies at a local Bible college.

"But it's not the only way to learn. This is where experience and skills come in," he said.

Even with his vast experience in schools, Mr Lim, who is married to a retired teacher and school counsellor, keeps an open mind.

"It doesn't mean once you're experienced, you can go in and start to change things," he said. "You have to gain the trust of the people you work with because you need them to work with you."

Educators, especially, need to keep up with the changing times and generations, he added.

"In this world, things are changing so fast. I tell my teachers - if you don't continue learning, then we can't teach the next generation. We need to have different ideas and perspectives to be innovative in teaching this new generation."

And that is why he visits bookshops wherever he goes. Books that are relevant to education and children interest him the most.

"These can be about classroom practices, assessment methods and how to be a team player," he said, adding that he has also told short stories from the Chicken Soup For The Soul series at school assemblies to motivate his pupils.

His latest read is a book, Creative Schools, by authors Ken Robinson and Lou Aronica, about how to engage students and help them develop a love for learning.

Said Mr Lim: "It's not about having a degree or not having, but whether you have that attitude to keep learning.

"Children today know a lot. But we have to help them be discerning, to know the right from wrong."