Evening two of the Intensive uses one number on the board and refuses to move it. The number is the baht amount you are willing to lose if the idea is wrong. Everything else is measurement. Learners who have traded for years still arrive wanting the quantity first — a round lot, a size that “looks serious” — and the stop second, nudged until the loss feels acceptable. We run the sentence in the other direction.

The same 2,000 baht

Suppose you will lose 2,000 baht if price reaches the invalidation, and not more. On the first practice chart the distance from the planned entry to that level is one baht. The quantity is 2,000 divided by 1, which is 2,000 shares, ignoring commissions for a moment so the relationship stays visible. On the second chart the level that actually proves the idea wrong sits four baht away. The same 2,000 baht now buys a quantity of 500 shares. The second idea is not worse. It is wider. Wide and large together are how a single chart spends a weekly cap before lunch.

Someone at the March table called the 500-share result timid. Arun asked him to move the invalidation closer so the quantity could grow, and then asked whether the closer line was still the price that proved the idea wrong. It was not. It was the price that made the size feel respectable. That line came off the page.

Commissions and the habit

In the room we add a rough commission and slippage figure only after the relationship is clear, and we add the same figure to both examples so it does not become a hiding place. The habit we want is dull: measure distance, divide the planned loss by that distance, write the quantity, and if the quantity looks embarrassingly small, respect the distance or abandon the idea. Do not edit the level to flatter the quantity.

The figures above are classroom arithmetic for seeing how distance changes quantity. Your broker’s lot size and fees will change the exact count. They will not change the direction of the rule: a wider invalidation asks for a smaller size.

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