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Fodor
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 Darwin
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 Evolution--论文代写范文精选

在达尔文之前,有两种观点,对于生物的特征，上帝创造了他们这些特质。达尔文提出,生物并不总是拥有一定的特质，他们进化从早期的生物。今天的生物的特征是那些帮助他们的祖先传承这些特征。下面的essay代写范文进行讲述。

ABSTRACT
Jerry Fodor argues that Darwin was wrong about "natural selection" because (1) it is only a tautology rather than a scientific law that can support counterfactuals ("If X had happened, Y would have happened") and because (2) only minds can select. Hence Darwin's analogy with "artificial selection" by animal breeders was misleading and evolutionary explanation is nothing but post-hoc historical narrative. I argue that Darwin was right on all counts. Until Darwin's "tautology," it had been believed that either (a) God had created all organisms as they are, or (b) organisms had always been as they are. 

Darwin revealed instead that (c) organisms have heritable traits that evolved across time through random variation, with survival and reproduction in (changing) environments determining (mindlessly) which variants were successfully transmitted to the next generation. This not only provided the (true) alternative (c), but also the methodology for investigating which traits had been adaptive, how and why; it also led to the discovery of the genetic mechanism of the encoding, variation and evolution of heritable traits. Fodor also draws erroneous conclusions from the analogy between Darwinian evolution and Skinnerian reinforcement learning. Fodor’s skepticism about both evolution and learning may be motivated by an overgeneralization of Chomsky’s “poverty of the stimulus argument” -- from the origin of Universal Grammar (UG) to the origin of the “concepts” underlying word meaning, which, Fodor thinks, must be “endogenous,” rather than evolved or learned. 
KEYWORDS: adaptation, Chomsky, consciousness, counterfactuals, Darwin, evolution, fitness, Fodor, learning, lexicon, mind, natural selection, poverty of the stimulus, Skinner, Turing, underdetermination, universal grammar

This is true, but I think everyone (including Darwin) already recognized it. The principle of natural selection is not meant to be a "law." Before Darwin, there were two views of why organisms have the traits they have: (i) God created them with those traits (creation theory) or (ii) creatures are as they always were ("steady state" theory). Darwin suggested the third (and true) alternative which is that, no, creatures did not always have the traits they now have: They evolved that way, in real time, from earlier creatures. Their traits vary from creature to creature, and some of the variants are heritable. So the (heritable) traits of present-day organisms are those that helped their ancestors pass on those very traits more successfully than other (heritable) variants in that ancestral environment: The methodological consequence of this original and productive insight is that biologists should investigate which traits are heritable, what the mechanism of the heritability is (it turned out to be genes), and what it was in the ancestral environment that made some traits more successfully transmissible than others (and how, and why).

That today's heritable traits are those of yesterday's heritable traits that caused the creatures inheriting them to be more successful, in their environment, in surviving and reproducing thanks to (some of) those very traits, is indeed a tautology -- once you realize the consequences of the fact that there does indeed exist such a heritable variation/retention process; but not without that realization. And that is the realization we owe to Darwin. It was neither obvious before Darwin -- nor is it true a-priori, as a matter of necessity -- that there exists heritable variation underlying creatures' traits, and that the survival/reproduction advantages -- i.e., the adaptive advantages -- of those heritable traits in creatures' ancestral environments were what shaped the current traits of creatures across time. Hence it was not obvious that that was what you had to investigate if you wanted to know what traits had evolved in what environments, as a result of what adaptive advantages. But the general principle itself does not identify any particular trait of any particular creature in any particular environment.

Notice that there has been no need at all to mention either "Natural Selection," which is just a metaphor, nor "fitness," which really just means "the relative success of the heritable variants in a given environment." Success in survival/reproduction -- determined by the effects of the environment on the distribution of heritable traits in the next generation -- is what replaces the intentional choices of the selective animal breeder by a mindless process. More generally, the case of the effects of the intentional choices of selective breeders is just a very special -- and until very recently, highly atypical -- case of this same, general, mindless process, namely, the transmission success of heritable traits being determined by the causal contingencies of the environment in which they occur: Mindful animal breeding is just one of those environments. Moreover, mindfulness itself is just one -- or several -- of those evolved, heritable traits: It is often the traits of one organism that constitute part of the environment of another organism, whether within or between species.

It is true (and has been pointed out by many others too) that both Skinner's reinforcement learning and Darwin's adaptive evolution are based on random-variation plus differentialretention-by-consequences (Catania & Harnad 1988). But the analogy ends there. Skinner tried to explain the "shape" of all behavior as having been determined by random-variation (in responses emitted by the organism) plus reward ("selection by consequences"). Skinner even has an (implicit and unintended) analogy with animal breeders' artificial selection vs "natural selection": the analogy between animal trainers' "artificial reinforcement" (for doing the performance tricks) and the "natural reinforcement" in our (and other animals') natural lives that "rewards and trains us" to perform as we do. 

But most natural behavior is not explained or explainable as the result of shaping by Skinnerian reinforcement. In particular, the (universal) grammatical "shape" of language (UG) is not learned or learnable by children through reinforcement training, because of the "poverty-of-thestimulus": What the child hears and says, and what corrections (reinforcements) it receives during its brief language-learning period, are demonstrably too underdetermined to be able to learn UG from -- either via Skinner reinforcement learning or via any other learning mechanism. There just are not enough data (especially negative data: errors and error-corrections), or time (Chomsky 1980). The same, however, is not true of the evolution of heritable biological traits: For the evolution of today's organisms' heritable traits (their gene pool) there has been plenty of time, and of positive and negative data, in the 4 billion years since the "primal soup" (Dawkins 1976). 

In other words, there is no evolutionary "poverty-of-the-stimulus" problem with the evolution or evolvability of heritable traits, through random variation plus retention as determined by their adaptive consequences. (My guess is that Fodor, in his heart of hearts, thinks that there is such a povertyof-the-stimulus problem with the evolution of biological traits, and that that is what motivates his scepticism about both learning and evolution! Fodor & Pylyshyn 1988) Four billion years is plenty more time and data than the child's c. 4 language-learning years for evolving all heritable traits. It is not clear, though, that even that is enough time or data to evolve UG! But that's a very special case. 

Chomsky (1959) could have refuted Skinner (and did) with a lot more than just that: Reinforcement learning does not explain the "shape" of most nontrivial behavior, probably because a lot of human and animal behavior is not the result of reinforcement learning during the lifetime of the organism. Some of it evolved earlier; and some of human behavior is taught, or self-taught, via reasoning. Besides, even behaviors that are learnable via reinforcement learning are not explained until one provides the internal design of the learner that is capable of learning them (via reinforcement learning): Some behavior may indeed be learnable through trial-and-error-correction alone, but how do we have to be built in order to be capable of learning it through trial-and-error-correction alone?

Our cognitive capacities (including our learning capacities -- inasmuch as they are heritable rather than acquired traits) are simply a subset of the traits that evolution (including neural and behavioral evolution) needs to account for. These cognitive capacities are far from having been accounted for yet; but there is nothing at all in Fodor's critique of Darwin (or even of Skinnerian reinforcement learning) that implies that they will not or cannot be accounted for: There is no "poverty-of-the-stimulus" argument here. And the "intentionality" argument against PNS is not an argument, but a misunderstanding of Darwin's "selection" metaphor.（essay代写)

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