http://blogs.psychologytoday.com/blog/one-among-many/200901/troubles-with-determ\
inism

The author fails to explain the context within which EHR occurs. The
instances in which I have heard people use the phrase "everything
happens for a reason" they were referring to supernatural agency. They
believed that the events in their life were part of "god's plan".
This is not a true determinism since a god might choose to intervene
or not. It is also usually presumed that god intervenes (has a plan)
only for the true and faithful.
There is also a fatalism here, since if there is a plan, it would be
foolish to act on one's own and disrupt the plan.
<<<Instead, they are using the term "randomness" as a shortcut
description of a jumble of systematic effects that is too complex to
be unpacked. In other words, to determinists the notion of randomness
is an epistemological trick. It expresses their ignorance of
everything that lies beyond the boundaries of their theories.>>>
No, only that which lies beyond their direct observation.
<<<In scientific psychology, there is constant friction between
deterministic theories, such as behaviorism (or any other theory
describing "mechanisms") and theories stressing human agency. What
academic psychology seems to be telling us is that human behavior
follows scientifically detectable laws and that at the same time we
have the power to choose and change apart from these laws.>>>
This misrepresents the friction between behaviorism and other
psychological theories.
Radical Behaviorists believed that only behavior need be considered
when treating a patient. Later, it became widely acknowledged that
cognition has a major role in shaping a person's experience. The
resulting blending of these approaches is CBT Cognitive Behavioral theory.
It would be a mistake to say that Cognitive theory stresses "Human
agency" that is "apart from scientific laws".
In my experience, cognitive theorists are either neutral or lean
heavily in the direction of determinism.
The practical reason for this lean toward determinism is that if a
person has human agency that is beyond scientific law then they can
simply choose not to be mentally ill. If this is the case and they
choose to remain mentally ill then they are deserving of the stigma
attached to their condition.
By viewing mental illness through the lens of determinism, the
mentally ill are spared the stigma and condemnation of their fellow
human beings.
Determinism doesn't mean that humans don't have choice. Determinism
means that their choices are circumscribed by genetic predisposition,
environment and chance encounter.