We are used to thinking in a linear fashion. We are born, grow old, and die, and many of us spend all our money in our lifetime. We dig resources out of the ground, fashion them into products, use them, and throw them away.

Native cultures often thought in cycles, not straight lines. They lived according to the seasons, and honored rather than pillaged the earth. The Iroquois thought about impacts on seven generations of descendants before making important decisions.

With the planet approaching a population of nine billion, many think it's time to think circular. Ellen MacArthur, a British sailor, thought hard about efficient resource management while beating a world record sailing solo around the globe, in 2005. Five years later she launched the Ellen MacArthur Foundation, which "aims to accelerate the transition to a circular economy, a systems level redesign which offers the opportunity to harness innovation and creativity to enable a regenerative economy."

What does all that mean?

It is about attention to how we design, manufacture, use and dispose of all the physical things in our world. We need to shift our mindset to thinking in cycles for both our biological things, such as coffee, and our technological things, such as cellphones.

In the case of our food and other biological material, we farm it using pesticides and without regard for soil regeneration. Much of it is wasted before arriving all the way to a consumer's mouth. And then we dispose of our organic waste without composting.

All of this can be improved through innovation. We can extract biochemical feedstock from food waste, for example, and use it as a resource. We can compost and use enzymes as a substitute for certain chemicals.

On the technology side, we dig fuel and minerals out of the ground, we ship them to a place where parts are manufactured, we ship the parts somewhere else and assemble them into products, a service provider then offers them on the market, and they are bought and used. As soon as a newer model comes out, we throw away our old one without much thought to where it's going or the waste involved.

In many cases, what we want is the service provided by a product, not necessarily the product itself. We might be happy to pay for getting from point A to point B, and not necessarily need to purchase the vehicle that gets us there. We could prefer to purchase a contract for illumination of our factory, and let the lightbulb manufacturer-turned-service-provider worry about when to change the bulbs. That kind of change would incentivize manufacturers to design products that last, and that can be repaired and repurposed.

The Ellen MacArthur Foundation hopes to inspire thinking around the redesign of these systems. We can manufacture products that last much longer, rather than focusing on the race to the next model. We can fix our toasters when they break, instead of throwing them away. If you haven't heard of it yet, check out ifixit.com, a community that stands for the "right to repair" and hopes to deconstruct every product and publish a free manual on how to fix it. The New York State legislature is considering a "Fair Repair" bill that would require manufacturers to provide owners and independent repair businesses with fair access to service information, security updates, and replacement parts.

When we really are done with a product, we can redistribute it on eBay or at Goodwill so that someone else gets a chance to use it further.

Finally, as a last resort, we can recycle the waste from the products we throw away. That sometimes requires redesigning the products so they are recyclable, and always requires collecting waste, sorting it, and having the technology to process each waste stream. In the US, Walmart and many of its biggest suppliers, including Coca-Cola and PepsiCo, were so frustrated with cities not having the funds to create recycling programs that they set up the Closed Loop Fund to help speed up the process.

Our linear way of extracting, producing and consuming energy can be replaced by circular, renewable energy, bringing all kinds of benefits. But again, the shift requires plenty of innovation and a systems level redesign.

"A circular economy is one that is restorative by design, and which aims to keep products, components and materials at their highest utility and value at all times," reads the Ellen MacArthur Foundation's website. It also means eliminating the concept of waste, with materials ultimately re-entering the economy at end of use as valuable technical or biological nutrients.

By the way, moving from a linear to a circular system provides a tremendous economic opportunity. According to research by the Ellen MacArthur Foundation and McKinsey & Company, the cost savings alone are worth billions of dollars.

There are already numerous examples of businesses globally that are taking advantage of the economic opportunities offered by transitioning to a circular economy. The next challenge is to scale up circular economy activities more broadly, and doing that will require greater awareness of the opportunities across businesses globally.

We have all the tools to shift to a circular economy. Unfortunately, we lack the awareness, and the will, to do it. Drumming that up is the challenge of our time.