A good way of thinking about theory is to consider theory as a lens. For example, when you go to the eye doctor for a new set of eyeglasses, the doctor asks you to look at a collection of letters through samples of different lenses. Each lens provides you with a different view -some lenses make the letters clear and organized, whereas others leave them fuzzy and distorted. Just as each lens dramatically shapes the way that you see the same view, each theory shapes the way that you interpret the world. Not all theories are successful in helping you see a social phenomenon more clearly. Indeed, some theories that aim to simplify complex information can end up making it more complicated. However, sometimes the right theory can help you see information in an entirely new light, just as the correct lens allows you to see with precise detail. In this way, theories are tools for critical and contextual analysis.

As the term agriculture usually brings to mind images of green fields of grass and vegetables, many people are surprised to hear that this industry is a significant contributor to the rising levels of greenhouse gases in the atmosphere. One of the main issues is that to make a piece of land suitable for cultivation, the trees that cover it are removed. This poses a serious problem because trees function as carbon sinks, with the average tree absorbing just over 21 kilograms of carbon dioxide from the atmosphere each year. This means that clearing land for agriculture prevents the future capture of carbon by the trees that once grew there. The role of agriculture in global warming becomes apparent when you consider that approximately 15 billion trees are being cut down annually, and around 90 percent of these are lost to create new fields and pastures. It's a case of addition through subtraction. Each tree lost allows more carbon to remain in the air.

Scientific knowledge cannot account for correct aesthetic appreciation of nature because science represents natural objects as members of a specific class, rather than as individual entities. The science-based approach claims that aesthetically relevant properties are only those properties that all members of a natural kind share with each other. But this is not true. When we experience nature, we do not experience it as species, but as individual objects. And as separated into individual objects, nature can have aesthetic properties that are not entailed by its scientific description. Natural science can explain, for instance, the formation of the waterfall, but it has nothing to say about our experience of the majestic Victoria Falls when viewed at sunset, its reds and oranges countless and captivating; geology can explain the formation of the Ngorongoro Crater in Tanzania, but not its painful and breathtaking beauty at sunrise, the fog slowly lifting above the crater and a lone hippopotamus dark and heavy in the lake.