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A Tale of Perceptual Twists

A most amiable bridge playing professor of optics peered through coke bottle lenses at the ethics committee chair, an angry-red chain-smoker who smash banged his gavel and steamed like a skip bidder scorned.

The professor's voice warmed to a sincere plea of innocence. "I'd sooner play pairs without 3NT in my bid box than use these glasses to cheat."

"X-ray!" brayed the chairman.

"Not my field," the professor of optics demurred.

"Peeker!" cried the chairman. "Case in point."

The professor calmly examined Prosecution Exhibit I:

LP10a.gif (18002 bytes)

"I led the spade five. Partner won with the queen, and returned a spade to declarer's ace. Next, a heart to the king and partner's ace. Then a spade to my jack, all followed.

"I cashed my good spade, collected clubs all around. Partner signaled with the five.

"I guarded hearts; partner guarded diamonds. I, West, was on lead and a double squeeze loomed:

LP11.gif (19557 bytes)

"I played the club queen, breaking the squeeze."

"Effortlessly!" fumed the chairman.

"Quite naturally," mused the professor.

"Please note," said the professor. "Each bridge hand of thirteen cards contains one odd single suit and three even holdings; or, one even single suit and three odd holdings."

"Get to the fancy glasses," barked the chair.

"These lenses concentrate my vision on the two closed hands in every defensive position."

The professor shifted focus. The committee chamber vanished from sight and consciousness. Lost in thought the professor considered...


The numbers that represent
in the two concealed hands.


    The silent professor reflected upon Exhibit I:

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When all four numbers of a prism are even:

  • The closed hands have the same single suit


  • The single suits have the same parity.

Partner's prism signal promised an odd single suit- spades

Partner...odd spades

{ 6-6-8-6 }

Declarer...odd spades


"Peekaboo!" the chair intruded.

The professor resurfaced. "The prism signal revealed declarer's shape: 3=4=4=2. Declarer had discarded a club. The club queen sprung to my thumb."

"A defender signaling declarer's distribution. Horse feathers!" rumbled the chairman. Snorts escaped the members. The chair gaveled silence.

"Professor, you guess better than a mind reader in an eye patch. Take a gander."

Prosecution Exhibit II:

LP20.gif (19208 bytes)

"I remember," said the professor. "I led the heart king to declarer's ace. He drew trump in two rounds -East echoed. A club to dummy's queen, and a club to my ace. Partner signaled club length -three.

"I knew twelve of declarer's cards -six spades, five clubs, and the heart ace. Declarer's thirteenth was a heart or a diamond loser.

"He was about to discard two hearts or two diamonds on clubs; and trump his loser in the dummy. I had to cash my diamond ace or the heart queen:"

LP21.gif (9527 bytes)

"And quicker than 'Pass' after 'Please wait'  with a Yarborough, you grabbed the setting trick,"  said the chair.

The silent professor considered...


A prism that contains a couple of odd numbers and a couple of even numbers.

The black suits form the even couple.

The red suits form the odd couple.

The prism takes its name from the odd couple.


The silent professor reflected upon Exhibit II:

LP22.gif (23914 bytes)


The two concealed single suits always correspond to one of the prism couples.

Partner's prism signal revealed his single suit to be spades. In a Red Prism clubs and spades form the even couple.

When the single suits correspond to the even couple, their parity differs.

Partner...even spades

{ 8-3-7-8 }

Declarer...odd clubs


"Alert!" cried the chairman.

Aloud the professor explained, "I viewed declarer's hand through my Red Prism: odd in clubs, even elsewhere. Naturally, I cashed my heart queen"

Declarer: s-lg.gif (923 bytes) A Q J 10 5 3 h-lg.gif (916 bytes) A 4 d-lg.gif (910 bytes) --- c-lg.gif (940 bytes) K J 7 5 2

Deep in thought...

Dare I belabor the obvious for these gentlemen? Had partner held:

s-lg.gif (923 bytes) 8 6 h-lg.gif (916 bytes) 8 4 d-lg.gif (910 bytes) K J 9 8 6 2 c-lg.gif (940 bytes) 6 4 3

he would have used a prism signal to promise an odd single suit -clubs.

Partner...odd clubs 

Red Prism

Declarer...even spades


Declarer: s-lg.gif (923 bytes) A Q J 10 5 3 h-lg.gif (916 bytes) A d-lg.gif (910 bytes) 4 c-lg.gif (940 bytes) K J 7 5 2

Quick the diamond ace.

The professor, primed to deliver a closing argument, stood and stared at empty chairs. She raised her shades. She blinked; blinked again. No one. The jury was out but briefly.

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