Charity, population dynamics and the limits of rationality.

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Charity, population dynamics and the limits of
rationality.

• Lunch talk, IAS HUJI
• December 2006

2
Charity vs. Game theory agents character and
social order

• Rational agents
• Drive Egocentricity.
• Tools Training, stick and carrot policy. (tit
  for tat)
• Utopia Capital growth.
• Excellence
• Individuals.
• Moto everybody has a share (Milo Minderbinder,
  catch 22).
• Well at least is doing better.

• Good people
• Drive Good will.
• Tools Moral education
• Utopia no need for police and law enforcement.
• Equality.
• Community.
• Moto From each according to his ability, to each
  according to his needs (Marx, Critique of the
  Gotha Program)
• Never worked.

3

• R. Jehudah, R. Jose, and R. Simeon were sitting
  and Jehudah, the son of proselytes,
• sat before them. R. Jehudah opened the
  conversation, saying "How beautiful are the
• works of this nation (the Romans). They have
  established markets, they have built bridges,
  they have opened bathing-houses.
• R. Jose said nothing,
• but R. Simeon b. Johai said "All these things
  they have instituted for their own sake.
• Their markets are gathering-places for harlots
  they have built baths for the purpose
• of indulging themselves in their comforts they
  have built bridges to collect tolls from
• those who cross them."
• Jehudah, the son of proselytes, went and reported
  this conversation,
• and it came to the ears of the government
• (Babylonian Talmud, Shabat 33b).
• Are we looking for prosperity, or for piety?
• Also an intera-religion dilemma, where the
  mystical thought tend to give priority to the
  intentions and devotion, the establishment
  tends to prefer action, not devotion.

Spiritually authenticity oriented Thought Spe
ech Did (action)
normal religious establishment
Thought Speech Did (action)
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296 (????? 06)
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To what extent capitalism works?

• Thomas Malthus 1798
• An essay on the Principles
• of population
• Population growth is exponential (geometric
  series).
• Resources (food and other needs) grow only
  linearly.
• The ultimate result should be a catastrophe
  famine, war or disease.

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Malthus against the Poor laws

• The poor laws of England tend to depress the
  general condition of the poor in two ways. Their
  first obvious tendency is to increase population
  without increasing the food for its support. A
  poor man may marry with little or no prospect of
  being able to support a family in independence.
  They may be said in some measure to create the
  poor which they maintain, and as the provisions
  of the country must in consequence of the
  increased population, be distributed to every man
  in smaller proportions, it is evident that the
  labor of those who are not supported by parish
  assistance will purchase a smaller quantity of
  provisions than before and consequently more of
  them must be driven to ask for support.

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Was Malthus right? (1)

• In fact, the population actually grow
  exponentially

Not enough for the poor in UK
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Was Malthus right (2)

• But the GDP grows even faster

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Was Malthus right (3)

• And the per-capita GDP
• Are we catalyze the growth ? (Das human
  capital)

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So, is rational planning for the future possible?
Is social engineering, based on rational
predictions, desirable? Are there cases where
it is better to be ignorant ?
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Buridans Ass

• Jean Buridan (1300-1358) an entirely rational
  donkey, placed exactly in the middle between two
  stacks of hay of equal size and quality, will
  starve to death since it cannot make any rational
  decision to start eating one rather than the
  other
• Mathematically speaking, for any space-time
  continuous algorithm that should map a
  continuum (like all point 0,1) to binary
  decision (say, 0 OR 1) and for any finite time
  T, there should still a finite region of nonzero
  measure that has not yet mapped into either 0 or
  1. (think about stretching a rubber band between
  2 points) Thus, if the decision making algorithm
  of the donkey is deterministic, it MUST allow for
  few starting point that leads to its starvation
  to death.
• Being rational may be dangerous to your health !!
  
• Relevant to ATD converters, desynchronized
  peripheral devices
• One may argue that this type of failure is not
  common in nature. However, there are other
  situations where the stacks of hay are hidden.
  E.g., when the wolf pops out from his cave at the
  evening to look for a prey, it may has no clue
  about where it should go.

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The E-Coli case small creature, no memory.

• Two types of movement swimming in straight
  lines and tumbling, determined by
  the flagellar rotation.
• In the absence of external stimulus, swimming
  is followed by tumbling, and the new
  swimming direction is
  determined at RANDOM.
  The bacteria acts as a random walker.
• Along the swimming, the bacteria measures the
  concentrations of attractants (usually food) and
  repellents (usually poisons). Thus it knows what
  is the GRADIENT does life becomes better along
  this direction, or worse?
• In the presence of a chemical gradient bacteria
  will chemotax, or direct their overall motion
  based on the gradient. If the bacterium senses
  that it is moving in the correct direction
  (toward attractant/away from repellent), it will
  keep swimming in a straight line for longer
  before tumbling. If it is moving in the wrong
  direction, it will tumble sooner and try a new
  direction at random.
• There is still a random component, even in the
  presence of gradient !!!!

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Noise vs. deterministic action

• Noise may help to avoid deadlocks (Buridan), to
  avoid being stuck in local maxima, to confuse
  predators (game theory).
• Of course, too much noise is harmful as it leads
  to waste of time and energy without any purpose.
  

Optimal noise level
Benefit
Noise
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Conjecture

• ANY PHYSIOLOGICAL AND MOVEMENT ACTIVITY IS
  CHARACTERIZED BY SOME LEVEL OF NOISE, CLOSE TO
  THE OPTIMAL NOISE FOR THAT ACTIVITY.
• Rational
• Life the ability to extract the benefits
  from spatio-temporal fluctuations. If evolution
  works, this ability has to improve with time,
  including not only the deterministic parts
  (detaction, memory) but also noise optimization
  (?).
• Some support from HRV data, but

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Bon Appetite !