If you've studied history, politics or economics you'll have no doubt heard of the 19th-century Utilitarian philosopher and economist, John Stuart Mill.

He was an early proponent of liberty, equality and women's rights. Way ahead of his time in many respects. And recently I stumbled across a quote of his of huge relevance if networking is part of your marketing approach.

“It is hardly possible to overrate the value, in the present low state of human improvement, of placing human beings in contact with persons dissimilar to themselves, and with modes of thought and action unlike those with which they are familiar.”

Mill was highlighting back in 1848 what social scientists have only recently been able to prove: that the most valuable human networks are diverse ones.

We may feel more comfortable networking with people who are like us. We may enjoy hanging around with “like-minded people” and having our opinions validated. But we get the most new ideas and new opportunities from people we know who are different to us and we don't hang around with all the time.

These “weak ties” to people who move in different circles to us and who have different opinions and experiences are easy to overlook or even avoid.

But since they move in those different circles, know different people and have different experiences, they're the ones most likely to bring different and new information and opportunities to us. Far more so than the people who think like us, act like us and know the same people as us.

So whenever you're networking: make sure to connect with people who are a bit different to your normal crowd. And keep those connections live. You don't need to be in regular contact, but you do need to stay familiar.

And ignore the advice of people who tell you to only connect to people on Linkedin who you already know. If you want new opportunities and ideas you need to expand the diversity of your network, not keep it narrow.