There's a fragment from an 1858 speech in which Lincoln uses lawyerly logic to rebut the arguments of slaveholders.

FORBES: In His Own Words

Insurance uses the logic of market economics to price the risk.

FORBES: Gun Liability Insurance: Still a Viable Proposal

Obama uses a warped logic of federal noblesse oblige to dispense a bag full of goodies from tuition tax credits, to a mortgage refinancing credit, to public works projects.

FORBES: Dear President Obama, You Can't Create Growth, But You CAN Suffocate It

Is the logic that Deolalikar uses powerful enough to express Gaussian elimination?

FORBES: A Beautiful Sausage

Finally, in an interesting twist of logic, he uses the existence of volunteers, of charitable activities, to prove that volunteers and charitable activity cannot solve problems.

FORBES: Hunting Hari: Judging Johann's Journalism

The fuzzy is the logic that this machine uses to cook rice, not the way the rice comes out when it is done.

FORBES: The Sociologist: Peter Bearman

Here is an example of crime logic at work: the cybercriminal identifies a target enterprise and uses the wealth of information on Facebook, LinkedIn and other social networks to map the organization.

FORBES: To Stop Cybercrime: Understand Crime Logic, And Adapt