One of the problems has to do with a failure to communicate. Below is a quote from the blog: The word machine usually means something made of metal and plastic, created by humans. I think Lithgow was using the term machine in the figurative sense, calling an enzyme a type of biological machine. This is not the traditional term to describe life, so it will bother the literalists who expect correct words. Bio-engineers often use enzymes within large tanks to make chemical. These enzymes are separated from the context of a cell and used as natural nano-machines. The author may have extrapolated from the bio-tank to the cell; many bio-nano-machines make a cell. The value of this POV, although unorthodox, makes it easier to explain why there is a microbial symbiosis in the human body. In engineering, entropy is connected the wasted energy within machines that is lost as irretrievable heat. This could be due to friction and many other factors. The high efficiency of enzymes implies low entropy bio-nano-machines. The symbiosis of microbes within the human body implies even further gains in efficiency , which means entropy is lowering even further. Life evolves in the direction of its molecular systems gaining efficiency thereby lowering entropy, with the microbe symbiosis just another way to increase efficiency and further lower machine entropy. There is a simple reason for this evolutionary direction toward lowering entropy; bio-nano machine efficiency. There is an equation in chemistry called the Gibbs free energy equation. G= H - TS; where G is the Gibbs free energy, H is enthalpy, T is temperature and S is entropy. It is possible for entropy to decrease within chemistry as long as the Gibbs free energy is favorable. It only requires that H has to be stronger than S at a given temperature. For example, if I took water and oil and mixed these well, I can maximize the entropy of the system. There will be chaos in the emulsion. The emulsion won't stay that way, since the two liquids will eventually phase separate into bi-layer order. This will occur because of the enthalpy of the hydrogen bonding and van der Waals forces will be stronger than the induced high entropy. The Gibbs free energy is favorable for the phase separation even at the expense of entropy. Life and cells are essentially water and organics, with there being a some degree of surface tension between the two. According to Gibbs free energy, because hydrogen bonding is so strong, the water;s enthalpy will tend to lower the entropy of the organics over long periods of time. This give evolution a slow but steady sense of direction. No matter how hard you shake the oil and water, over time the entropy will lower due to free energy. This may not be the case with all solvents for life, but it will be true with water since it hydrogen bonding is so powerful. If we get back to microbe and the human body, this reflects lowered entropy within the human machine due to that fundamental free energy push by water. Like evolving machines, steps forward tend to lower entropy.