I just wanted to make a simple illustration of how the collective outcome of two absolutely rational reasonings may turn out to be not so rational. And why cooperation makes people better off. If you have suggestions or ideas to improve this message, feel free to leave your comments here, or email me: alex.hints (at) gmail.com __ Alex Hint is the author of Will Google Buy Formula 1. Follow Alex Hint on g+: http://goo.gl/HmeCLV

1. 5 5 0 10 10 0 1 1
Dilemma
Prisoner’s
The

2. Or why cooperation
makes people better off.

3. Tom Jerry
Here’s two prisoners, Tom and Jerry:

4. Tom’s told:
– Here’s the deal…

5. (Yeah, Jerry’s offered the same deal)

6. (1)
If you rat each other out,
then each of you will serve 5 years in prison.

7. 5
(1)
If you rat each other out,
then each of you will serve 5 years in prison.
You rat Jerry out
5
Jerry rats you out

8. (2)
If you rat Jerry out,
and Jerry remains silent,
then you will go home free
and Jerry will serve 10 years in prison.

9. 0
(2)
If you rat Jerry out,
and Jerry remains silent,
then you will go home free
and Jerry will serve 10 years in prison.
You rat Jerry out
10

10. (3)
If Jerry rats you out,
and you remain silent,
then you will serve 10 years in prison
and Jerry will go home free.

11. 10
(3)
If Jerry rats you out,
and you remain silent,
then you will serve 10 years in prison
and Jerry will go home free.
Jerry rats you out
0

12. (4)
If you and Jerry both remain silent,
then both of you will serve 1 year in prison.

13. 1
(4)
If you and Jerry both remain silent,
then both of you will serve 1 year in prison.
1

14. rat Jerry out
remain silent
What should Tom choose?

15. rat Tom out
remain silent
(And what should Jerry choose?)

16. From the outsider’s perspective

17. 5
(1)
Tom rats Jerry out
5
Jerry rats Tom out
(2)
(3) (4)
0
Tom rats Jerry out
10
10
Jerry rats Tom out
0 1 1

18. 5 5(1) + = 10 10 0(3) + = 10
1 1(4) + = 20 10(2) + = 10

19. 5 5(1) + = 10 10 0(3) + = 10
1 1(4) + = 2
2 < 10
Which means, they would be better off,
if they both cooperated and remained silence.
(Both of them would serve 1 YEAR in prison.)
0 10(2) + = 10

20. From Tom’s perspective
(the same is true for Jerry)

21. I rat Jerry out
Jerry rats me out
(1) (2)
5 0
If I rat Jerry out:

22. 10 1
(3) (4)
If I remain silent:
Jerry rats me out

23. 5 0+ = 10 1+ = 11
If I remain silent:If I rat Jerry out:
5

24. 5 < 11
That is, if Tom and Jerry are purely rational persons,
they will surely rat each other out.
(And both of them will serve 5 YEARS in prison.)
5 0+ 10 1+ 11= =
If I remain silent:If I rat Jerry out:
5

25. But…
1 YEAR in prison is better then 5 YEARS in prison.
That is: the guys should have cooperated.

26. Conclusion

27. In the end of the day,
Cooperation
makes everyonebetter off.

28. Embrace
Cooperation!
Thank You!
S
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Texture credit: Lonnon Foster