Scotland is unique in that each clan has its own tartan.

Each tartan is different and everyone can trace their heritage back to the particular tartan their clan has always worn.

Except they can’t.

It was all made up in 1829 by two brothers from Surrey.

The patterns always existed, of course, but they had nothing to do with clans.

The oldest example of tartan is in the National Museum of Scotland in Edinburgh: a small scrap of wool, herringbone, tweedy cloth from around 300AD.

But it had no meaning, different Highlanders wore whatever cloth was available in their area, naturally weavers in different areas wove differing styles.

And over the years these tartan patterns came to be known as a particularly Scottish Highland cloth.

Then, in 1822, the theatrical King George IV paid a state visit to Edinburgh.

He wanted to see tartan everywhere, that was his fantasy of Scotland.  So suddenly every family wanted to own a tartan.

Seeing an opportunity, two brothers from Godalming in Surrey jumped at it.

They were born John and Charles Allen in Wales, but changed their name to the more Scottish-sounding Hay Allan, then to Sobieski Stuart.

They published a book called Vestiarium Scoticum.

They said this book was copied from a document dated 1721, which was itself a copy of a parchment from 1571, detailing the tartans worn by 75 different clans from the Highlands, the Lowlands, and the Borders.

The book, and the brothers, were received with open arms by Scots nobility.

It meant everyone could tell exactly what tartan they were entitled to and could proudly boast of their heritage by wearing it to formal gatherings.

The brothers were the toast of Scottish aristocracy, they were given wealth and land.

But not everyone was convinced. One of the most famous Scotsmen, Sir Walter Scott, wrote that the book “sounded like a tartan weaver trying to drum up trade”, and that “the idea of distinguishing clans by tartan is but a fashion of modern date”, and that “no Lowlander ever wore a clan tartan”.

But in 1832 Sir Walter Scott died and, with him out of the way, the brothers were able to release another book Costumes of the Clans. They even claimed to be the grandsons of Bonnie Prince Charlie.

Eventually, in 1895, The Glasgow Herald tracked down the supposed 1721 copy of the Vestiarium Scoticum.

The newspaper’s chemist wrote “The document bore evidence of having been treated with some chemical agents in order to give the writing a more aged appearance than it is entitled to.”

So, proof that it was a fake.

But none of that affected the “tradition” that the Sobieski Stuart brothers had started.

Even today, people with Scots ancestry come from all over the world to have their “clan tartan” made into a kilt in Edinburgh.

The need for a sense of belonging overrides facts and makes truth irrelevant.

Which is a great lesson for us, and worth remembering.

Daniel Kahnemann won the Nobel Prize for founding Behavioural Economics.

His book: Thinking, Fast and Slow summarized our thinking into intuitive (System 1) and deliberate (System 2).

System 1 is immediate and reactive (emotion). System 2 is slower and deliberate (reason).

Basically we make a decision with System 1 and justify it with System 2.

So for us the lesson is: sometimes the product is the most important thing but  sometimes the consumer is more important than the product.

And what someone wants to believe is often more important than actual facts.

As David Hume, another Scotsman, said over 200 years ago:

“Reason is, and ought only to be, the slave of the passions, and can never pretend to any other office than to serve and obey them.”

The post REASON IS THE SLAVE OF THE PASSIONS first appeared on Dave Trott's Blog.