The song is "Easy"

For years, our cat Shoken has had the lightest leap onto the bed at night. She's a big cat, about 15 lbs, but she's as light on her feet as a dancer. There's no more pressure on us where she steps than I'd expect from a mouse. We've wondered, where is she putting her weight?

Well I've finally figured it out.

Cats have achieved the ultimate goal of modern physics, the grand unified theory, and their superior knowledge gived them the ability to alter space, time, and gravity. Now most of you have probably seen your cat staring blankly at the walls, and wondered what they're seeing, and now we have an answer. The cat is staring across space and time to decide where and when to displace their weight. They are monitoring the hidden forces of the universe so as to use them to their best advantage.

When your cat needs to leap across amazing distances, walk across narrow beams, or perform delicate balancing acts inside the closet, they don't want to have their full weight around. A cat needs to walk lightly over brittle leaves or among dishes on the forbidden kitchen counter when stalking elusive food. They want to be nearly weightless, and thus decrease their chance of a dangerous or undiginified fall, or unwanted discovery. By manipulating space, time, and gravity, your cat shifts its weight elsewhere, enabling it to perform these acts of quiet stealth. At a fraction of their normal weight, your cat all but floats above these surfaces.

However, weight, as a function of matter and energy, must be conserved. They must therefore shift their weight to another point in space-time, preferably to a point when they could use a few extra pounds. Ever notice how hard it is to pick up a cat that is sleeping on the clean laundry, or how heavy the carrier gets when you're going to the vet? Have you found your cat seems to be almost impossible to shift away from the foodbowl? Your cat is using up some of the wieght they'd displaced. Likewise, the same cat who walked across the bed unnoticed a moment before can suddenly seem to put an unnatural amount of weight on your bladder as they stand on your stomach, asking for breakfast.

Most cats only shift their weight a little. A cat may displace their weight forward in time when they get ready to pounce through the air onto an opponent or a favorite just long/far enough ahead to give them extra weight when they land. A cat will walk at a minus wieght over a pile of warm laundry (which often has hidden holes and pockets in which they could be trapped if at normal weight) until they find the perfect item to contrast with their shedding, and then shift to plus weight to allow them to sink into it most efficiently. In all things the cat seeks balance.

Humans have to work hard to achieve the same sort of effects. In Aikido it's sometimes referred to as "heavy", and is considered an expression of ki, referred to in the west as universal energy or life-force. Generally only those who have devoted years to the study of the martial arts have any noticable ability to make themselves impossible to shift. Cats do it as a natural expression of their cat nature.

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