How far down the continuum of care does the investment manager's responsibility go? A better question would be 'why do we need principles to help us make responsible investments?', says Gerrit Heyns, partner at Osmosis Investment Management.

Let's face it, one of the unfortunate by-products of the ESG/sustainability debate is that many well-meaning people want so badly to find a magically direct connection between doing good and producing investment returns. And this in financial markets whose core construct is to channel capital initially and reward financial performance generally.

It's not that doing good is bad. That's not the point. The world will be better off as more of us consider social and environmental issues more deeply. It's that the desire for markets to make the distinction is flawed. People are blinded by a holy grail that doesn't exist.

We all know that the world is growing at an incredible rate. With an expanding middle class, demand is growing even faster. And as it does so, the resources we use to satiate demand are diminishing at an accelerating rate. The inconvenient truth is that population growth and its demands are creating an ugly unsustainable world.

What can the investment community do to help alleviate the problem? Well, the reality is that many large, publicly listed companies are well ahead of investors. They have been addressing many of these issues for decades. And further, financial markets have praised and priced their efforts all along the way. The markets work.

Cement is a good example. Holcim Cement is a global business based in Switzerland. To better compete in its market, it created a technology to manufacture cement more efficiently by burning wood chips in their kilns. Many people applaud them for their environmentally friendly practice, but they've been burning wood chips since the 1990s, well before it was cool to be sustainable.

Their objectives were purely economically driven. They lowered their energy costs. The result is that they are able to compete more effectively. This is forward thinking by management. No regulation required. No coaxing, just economic value creation. And by the way, the market has rewarded Holcim shareholders relative to their peers.

What is needed in environmental, social and governance (ESG) investing is more pragmatism. Return-oriented investors are rightly sceptical about overly subjective measures of sustainability. A recent academic study trying to connect corporate returns with sustainable actions examined corporate conference calls, counting the number of times sustainability words were mentioned. Some people might find that interesting (if not slightly odd), but it's hardly a practical metric to aid investment decision making or even connecting sustainability to returns.

Freeport McMoran is one of the largest producers of copper in the world. It's hard to put copper production into the category of an environmentally friendly endeavour in any way. It's ugly. But it is also one of the many metals we cannot do without for even the shortest time frame in our lives. From a purely pragmatic perspective, we must mine copper to live the lives we live, at every end of the economic spectrum. This kind of thinking is a prime example of pragmatic sustainability.

Why talk about Freeport? As one of the largest producers of copper, Freeport McMoran is as ugly as the next. But Freeport is one of the most resource-efficient producers of copper globally. That is, it uses less energy and water and creates less waste in generating a unit of revenue that most of the other copper producers in the world. It is pragmatically sustainable.

And like most resource-efficient corporations, Freeport exhibits higher return on assets, higher return on equity and better operating margins that most of its competitors. And guess what - the market pays it for those qualities and has done for as long as it has displayed them. The market rewards pragmatic sustainability and always has done. It's good business.

Investors should be searching for companies that are able to create more using less rather than counting words in a conference call. Why? The simple answer is that markets are reasonably efficient. They reward the qualities that greater efficiencies bring to a company, and rightly so. They also tend to be collectively suspicious of idealism - and again, rightly so.

Gerrit Heyns is a partner at London-based Osmosis Investment Management.