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  • Solid color t-shirts are 100% cotton; heather grey is 90% cotton, 10% polyester; charcoal heather is 52% cotton, 48% polyester
  • Ethically sourced
  • Slim fit, but if that’s not your thing, order a size up
  • 4.2 oz (145g), but if that’s too light, try our heavier Classic T-Shirt


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I Cooperate in the Prisoner's Dilemma
Designed by Lalaithion
You Cooperate? But that's not optimal! You should always Defect in the Prisoner's Dilemma, that's the Nash Equilibrium! Wait, what do you mean that you know that? If you know that, why would you Cooperate? Congratulations, another brain melted by wearing this shirt.

Unisex T-Shirt

I Cooperate in the Prisoner's Dilemma by Lalaithion