My attempt to describe the difference of emphasis in Ph.D. and Psy.D. seems to have intensified the issue of research and the nature of scientific inquiry and the art of clinical practice, whether in psychology and medicine. I am happy to see folks here really pulling out serious thoughts on the subject.
I will begin with the foremost Western pioneering neuroscientist, physiologist, mathematician, and philosoper Descartes. From his discourse on emotions (now belonging to affective and cognitive neuroscience), Descartes observed:
"It is true, there are very few men so wake* and irresolute, that they will nothing but what their present passion dictates to them. The most part have determinate judgements according to which they regulate part of their actions. And though oft times these judgements be false, and indeed grounded on some passions, by which the will has formerly suffered herself to be vanquished, or seduced, yet because she perseveres in following them then when the passion that caused them is absent, they may be considered as her own weapons, and souls may be thought stronger or weaker according as they do more or less follow these judgements and resist the present passions contrary to them. But there is a great deal of difference between the resolutions proceeding from some false opinion, and those which are only held up by the knowledge of the truth. Since following these last, man is sure never to acquire sorrow or repentance, whereas following the first, they are inseparably companions, after the error is discovered." (Passions of the Soul, 1649)
So, a informed discussion with regard to psychology's place among the natural sciences would begin with the scientific method. In so far as researchers apply the scientic method and using the priciples of parsimony to arrive at either deductive or inductive explanation, facts matter. On the other hand, in so far as the psychology as an art, in the sense that a kidney can't tell you how the person thinks, feels, etc., but that a brain could, let the brain speak and the clinician listening with a Shakespearian ear! Both the science (reliable knowledge) and art (compassion and attuneent) completes the clinician's mission.
Those of you who are not questioning the specific methodology (e.g. quantitative vs. qualitative, genetic vs. behavioral) and scientific epistemology (means, limits, and consilience) but resort to opine for or against psychology as a science really ought to study creative writing, not science.
Dr.GA2B