Why should there be a numerical parameter predictably increased by evolution? Why not look for a numerical parameter predictably increased by continental drift? or by prayer? by ostriches?
One of the key pieces of justification for FAI is the idea of “optimization process”. Evolution is given as an example of such process, unlike continental drift or ostriches. It seems natural to ask what parameter is optimized.
Just FYI, I interpret that question very differently than your original.
Why don’t you start with a simpler example, like a thermostat? Would you not call that an optimization process, minimizing the difference between observed and desired temperature?
Most of your rejections of suggestions in this thread would also reject the thermostat. An ideal thermostat keeps the temperature steady. Its utility function never improves, let alone monotonically. A real thermostat is even worse, continually taking random steps back. In extreme weather, it runs continually, but never gets anywhere near goal. It only optimizes within its ability. Similarly, evolution does not expand life without bound, because it has reached its limit of its ability to exploit the planet. This limit is subject to the fluctuations of climate. But the main limit on evolution is that it is competing with itself. Eliezer suggests that it is better to make it plural, “because fox evolution works at cross-purposes to rabbit evolution.” I think most teleological errors about evolution are addressed by making it plural.
Also, thermostats occasionally commit suicide by burning down the building and losing control of future temperature. (PS—I think the best example of evolutionary suicide are genes that hijack meiosis to force their propagation, doubling their fitness in the short term. I’ve been told that ones that are sex-linked have been observed to very quickly wipe out the population, but I can’t find a source. Added: the phase is “meiotic drive,” though I still don’t have an example leading to extinction.)
OK, if we replace “evolution” with “fox evolution”, and “increase” with “try to keep steady”, what parameter does fox evolution try to keep steady? Or am I missing the point of your analogy?
Do you mean to say that the expected inclusive fitness of a randomly selected creature from the population goes up with time? Well, if we sum that up over the whole population, we obtain the total number of offspring—right? And dividing that by the current population, we see that the expected inclusive fitness of a randomly selected creature is simply the population’s growth rate. The problem is that evolution does not always lead to >1 population growth rate. Eliezer gave a nice example of that: “It’s quite possible to have a new wolf that expends 10% more energy per day to be 20% better at hunting, and in this case the sustainable wolf population will decrease as new wolves replace old.”
Why should there be a numerical parameter predictably increased by evolution? Why not look for a numerical parameter predictably increased by continental drift? or by prayer? by ostriches?
One of the key pieces of justification for FAI is the idea of “optimization process”. Evolution is given as an example of such process, unlike continental drift or ostriches. It seems natural to ask what parameter is optimized.
Just FYI, I interpret that question very differently than your original.
Why don’t you start with a simpler example, like a thermostat? Would you not call that an optimization process, minimizing the difference between observed and desired temperature?
Most of your rejections of suggestions in this thread would also reject the thermostat. An ideal thermostat keeps the temperature steady. Its utility function never improves, let alone monotonically. A real thermostat is even worse, continually taking random steps back. In extreme weather, it runs continually, but never gets anywhere near goal. It only optimizes within its ability. Similarly, evolution does not expand life without bound, because it has reached its limit of its ability to exploit the planet. This limit is subject to the fluctuations of climate. But the main limit on evolution is that it is competing with itself. Eliezer suggests that it is better to make it plural, “because fox evolution works at cross-purposes to rabbit evolution.” I think most teleological errors about evolution are addressed by making it plural.
Also, thermostats occasionally commit suicide by burning down the building and losing control of future temperature. (PS—I think the best example of evolutionary suicide are genes that hijack meiosis to force their propagation, doubling their fitness in the short term. I’ve been told that ones that are sex-linked have been observed to very quickly wipe out the population, but I can’t find a source. Added: the phase is “meiotic drive,” though I still don’t have an example leading to extinction.)
OK, if we replace “evolution” with “fox evolution”, and “increase” with “try to keep steady”, what parameter does fox evolution try to keep steady? Or am I missing the point of your analogy?
Inclusive reproductive fitness.
Do you mean to say that the expected inclusive fitness of a randomly selected creature from the population goes up with time? Well, if we sum that up over the whole population, we obtain the total number of offspring—right? And dividing that by the current population, we see that the expected inclusive fitness of a randomly selected creature is simply the population’s growth rate. The problem is that evolution does not always lead to >1 population growth rate. Eliezer gave a nice example of that: “It’s quite possible to have a new wolf that expends 10% more energy per day to be 20% better at hunting, and in this case the sustainable wolf population will decrease as new wolves replace old.”