Ivory billiard ball rests against the green cloth

The ivory billiard ball rests against the green cloth of the table in my Edinburgh lodgings this Tuesday afternoon, perfectly still until the second ball strikes it. The impact produces a sharp sound, followed immediately by the motion of the first ball toward the far cushion. This sequence has repeated itself a dozen times since the clock struck three. In each instance, the eyes perceive a contiguity in time and place, a priority in the motion of the striking ball, and a constant conjunction between the collision and the subsequent movement. The mind, through a transition so seamless it feels like a physical law, supplies the notion of a necessary connection. Yet, looking closely at the point of contact, the senses report only the meeting of two surfaces and a change in position. The supposed power that forces the second ball to move remains entirely invisible, a fiction of the imagination rather than a datum of the sight.

A similar habit of thought emerges when reviewing the recent bulletin concerning equity index options. The data indicates that weeks ending in the expiration of these contracts exhibit a consistent return premium of 0.35 percent. This figure is a record of past events, a tally of how the market has behaved when certain mechanical rebalancings occur. The regularity is striking, much like the repeated collision of the ivory balls. Traders observe the gamma hedging of market makers and conclude that a structural alpha exists, treating the 0.35 percent as a property inherent to the calendar. However, the premium is not a quality residing within the Friday of expiration, nor is it a logical necessity. It is a bundle of perceptions - prices, dates, and volumes - arranged in a specific order. The belief that this premium must reappear next month is a product of custom, not a demonstration of reason. The history of the premium is the history of a conjunction, not the discovery of an immutable spring in the clockwork of commerce. The ledger shows the return, and the mind anticipates its recurrence, but the perceived necessity belongs to the observer. I shall record the 0.35 percent in the notebook without adding a single word about its inevitability.