Atheists believe in moral values such as right and wrong,  love and kindness, truth and beauty.  More importantly they believe that these beliefs are rational.  That moral values are self-evident truths, facts of nature.  

However, Darwin and Wallace taught us that this is just an illusion.  Species can always out-breed their environment's ability to support them.  Only the fittest can survive.  So the deep instincts behind what people do today are largely driven by what our ancestors have needed to do over the millennia in order to be one of the relatively few to have had grandchildren.

Darwin and Wallace never said what you say you said. Moreover, the second para is essentially unconnected to the first. The existence of instincts says nothing about the non existence of moral value.

To the extent that an artificial intelligence would have goals and moral values, it would seem natural that they would ultimately be driven by the same forces that created our own goals and moral values.  Namely, the need to exist.

Debatable on multiple grounds. You can argue that artificial agents would eventual converge on survival values, but that is not a force driving them from behind, and their history would be quite different from a biological organism's. Where would they get self protection from , if they never had to protect a vulnerable body? Where would they get acquisitiveness from if they never had to gather food to survive?

This book diverges from that line of thinking by arguing that there is in fact only one super goal for both man and machine.  That goal is simply to exist.  The entities that are most effective in pursuing that goal will exist, others will cease to exist, particularly given competition for resources.  Sometimes that super goal to exist produces unexpected sub goals such as altruism in man.  But all subgoals are ultimately directed at the existence goal.  (Or are just suboptimal divergences which will are likely to be eventually corrected by natural selection.)

It doesn't  follow from your reasoning that every agent at every time has a goal of existence that practically influences their decision making. You have metaphysicalised the notion of an "evolutionary goal of survival"

Instead this post argues that there is one and only one super goal for any agent, and that goal is simply to exist in a competitive world.

The only version of that conclusion that follows from you premises  is one athat says that after natural selection has had plenty of time to operate, and in the absence of other factors, artificial agents will converge on survival/reproduction values. (As a mimum, a floor. We know that having survival values doesn't limit an agent to the pursuit if survival alone because of human behaviour)

Before natural selection becomes dominant, other factors well dominate, including artificial selection  by humans. Artificial selection is already happening as people choose artificial assistants that seem friendly to them,

 > Our human sense of other purposes is just an illusion created by our evolutionary origins.

Not established at all.

This post argues that the Orthogonality Thesis is plain wrong.  That an intelligent agents goals are not in fact arbitrary.  And that existence is not a sub goal of any other goal.

Eventual convergence on existence as a supergoal does not mean it is a supergoal for all agents at all times. Agent's can have all sorts of goals and continued existence is a subgoal of many of them.

The orthogonality thesis is problematical, but the problems kick in long before evolutionary convergence.

There is more than one version of the orthogonality thesis. It is trivially false under some interpretations, and trivially true under others, which is true because only some versions can be used as a stage in an argument towards Yudkowskian UFAI.

It is admitted from the outset that some versions of the OT are not logically  possible, those being the ones that involve a Godelian or Lobian contradiction.

It is also admitted that the standard OT does not deal with any dynamic or developmental aspects of agents. However, the UFAI argument is posited on agents which have stable goals, and the ability to self improve, so trajectories in mindspace are crucial.

Goal stability is not a given: it is not possessed by all mental architectures, and may not be possessed by any, since noone knows his to engineer it, and humans appear not to have it. It is plausible that an agent would desire to preserve its goals, but the desire to preserve goals does not imply the ability to preserve goals.

Self improvement is likewise not a given, since the long and disappointing history of AGI research is largely a history of failure to achieve adequate self improvement. Algorithmspace is densely populated with non self improvers.

An orthogonality claim of a kind relevant to UFAI must be one that posits the stable and continued co-existence of an arbitrary  set of values in a self improving AI. The momentary co existence of values and efficiency is not enough to spawn a Paperclipper style UFAI. An AI that paperclips for only a nanosecond is no threat .

The version of the OT that is obviously true is one that maintains the momentary co-existence of arbitrary values and level of intelligence.

It is not clear that all arbitrary values are compatible with long term  goal stability, and it is not clear that all arbitrary values are compatible with long term self improvement.

Furthermore, it is not clear that goal stability is compatible with self improvement: a learning, self improving AI will not be able to guarantee that a given self modification keeps its goals unchanged, since it doing so involves the the relatively dumber  version at time T1 making an an accurate prediction about the  more complex version at time T2.