Solitaires differ widely in the opportunities they afford for the exercise of skill. Some are purely mechanical, while others torture the mind.
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Cal's Brain Strain is a variation of Calculation Solitaire.
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"Calculation stands at the top of the list of games that give opportunity for skill."
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So says the world's leading authority on cards & gambling, John Scarne, in his classic work, Scarne's Encyclopedia of Card Games. You've played all the other solitaires - but are you good enough for the king of them all?
