The wheel was undoubtedly the development on the sled idea. Previously, the load used to be laid on transverse logs and rolled along on these. The logs had to be picked up behind, carried forward and laid underneath again.  No easy job, we should say.

And everyone has heard about the wheel as the symbol of a brilliant discovery. But few have realized that the wheel itself is quite a useless affair. It is the wheel and axle system that actually works.

While being functionally similar to the rolling log for the transportation purposes, the wheel and axle system is thousand-fold superior to the latter in terms of efficiency: you needn’t carry anything forward and lay down — just pull the cart ahead. And the wheeled chassis is much lighter than a heap of solid logs.

The wheel and axle system owes its fantastic efficiency to its dualistic nature — similar to Yin vs. Yang, or the unity and struggle of opposites, discovered by Ancient Greek dialecticians. The system’s two articulated parts have opposite properties individually; but combine to produce a set of striking consumer qualities that are unattainable in principle for systems with degraded internal organization. Like that log above.

Indeed, the log is long, heavy, and of the same diameter throughout its length. And its diameter is chosen with two mutually contradictory considerations in mind: on the one hand, it should be thicker for easier rolling and, on the other hand, thinner for ease of dragging it ahead and putting under the sled.

The wheel is short (commonly understood to be "narrow"), lightweight, and big in diameter. The axle is long, lightweight, and very small ("thin’") in diameter. The wheel and axle system is as wide as you need, and of any diameter that may be requird at specific places (a "big" wheel and a "thin" axle) while being quite lightweight. And, what is damn specific, you needn’t carry and put anything anywhere.

In providing much faster riding with dramatically lighter weight and excluding the stupid work of dragging logs ahead and laying them under the sled, the wheel and axle system is philosophically a twin of the IEM System.

One which is internally a superposition of two complementary entities of opposite purpose and properties while being monolithic at its outer perimeter.

In the business process automation area, a system with primitive internal organisation (a sled on logs) is quite similar to the decades-old ERP, WMS, CRM, MES, and other ABC IT fossils.