Is psychology a science?  

Increasingly, the respect of science (and scientists) by the public has been dropping and a part of that reason is because the line of what science is has become fuzzy. If economics calls itself science, well, the public knows they don't know what they are talking about, so maybe it applies to climate science too. Is sociology science?  What about parapsychology?

If the definition of science becomes relative, then so does acceptance of science, in a slippery slope world, so we can't expect people will accept FDA findings as science if political science is funded by the National Science Foundation and the public knows that isn't scientific at all.

Writing in the Los Angeles TimesTimothy Wilson,  professor of psychology at the University of Virginia, says the other sciences are using an artificial metric - and being mean.   He wrote, "There has long been snobbery in the sciences, with the "hard" ones (physics, chemistry, biology) considering themselves to be more legitimate than the "soft" ones ( psychology, sociology)."

Well, his irritation is understandable. He cites an anecdote where a biologist dismissed the social sciences but, like science itself, 'hard' science has become colloquialized, almost as if they mean 'difficult' rather than physical.  When I graduated college no one considered biology a 'hard' science, those were limited to just the physical fields.

Wilson knows it isn't just scientists who dismiss the social fields. Charles Lane, writing in the Washington Post, says the move by Congress to eliminate political science from the National Science Foundation doesn't go far enough.  It should eliminate all social science funding.
Though quantitative methods may rule economics, political science and psychology, these disciplines can never achieve the objectivity of the natural sciences. Those who study social behavior — or fund studies of it — are inevitably influenced by value judgments, left, right and center. And unlike hypotheses in the hard sciences, hypotheses about society usually can’t be proven or disproven by experimentation. Society is not a laboratory.
Gary Gutting, professor of philosophy at the University of Notre Dame, writes in the New York Times 
While the physical sciences produce many detailed and precise predictions, the social sciences do not. 
Given the limited predictive success and the lack of consensus in social sciences, their conclusions can seldom be primary guides to setting policy. At best, they can supplement the general knowledge
We all knew those things, of course.  It's not to say they don't have value, obviously they do, but engineering also has value. It is not science.  Teaching has terrific value.  It is not a science.  Same for mathematics and economics.  Lots of fields have applied benefits and consumer marketing shows that applied psychology is darn rigorous, even though it isn't science.  Why are psychologists so touchy if their offices are not in the science buildings?

Wilson seems to confuse surveys and statistics with science.  Why stop there if that is all it takes to be a scientist? I write about science every day, I know a decent amount of science, one of my degrees is in psychology, yet I have never once called myself a scientist. In 1987, psychology was not considered science the way people commonly regard science.  It was a social science and even then I considered it a proper name rather than a definition - like String Theory or Military Science.

I love military science.  Like learning Latin, it is rare enough today that should I choose to get a Ph.D., it would be in that.  But would that make me a scientist?  No, it would mean I am studying how people behave(d) and I am using data, but in a real-world condition it would be foolish for a General to listen to a Ph.D. in military science. War is a poor laboratory, just like society is.

Wilson lists examples like cognitive behavioral therapy and says those have helped people - and he is right,  the efforts of Albert Ellis and Aaron Beck to modernize thinking 50 years ago have done wonderful things for untold people, but so have self-help books.  Are the people writing self-help books scientists?   His other claims, like claiming benefits of the stereotype threat hypothesis, are instead the subjective nonsense that critics are talking about when they dismiss psychology today - he would have been better off leaving out that one.  Same with the "Scared Straight" program, which he says psychologists showed did not work.  What he leaves out is that psychologists were the ones who said it would work in the first place.

Dr. Alex Berezow, a microbiologist by degree, says it is not bullying that causes other fields to lump social sciences outside science, it is intellectual frustration.  He doesn't contend the field has no important insights
Making useful predictions is a vital part of the scientific process, but psychology has a dismal record in this regard. Just ask a foreign policy or intelligence analyst.

To be fair, not all psychology research is equally wishy-washy. Some research is far more scientifically rigorous. And the field often yields interesting and important insights.
it just is not science in the way that scientists and the public recognize science.
Why can we definitively say that? Because psychology often does not meet the five basic requirements for a field to be considered scientifically rigorous: clearly defined terminology, quantifiability, highly controlled experimental conditions, reproducibility and, finally, predictability and testability.
We can all pick nits about how much of biology satisfies those criteria, and physics also. Generally, science is about explaining (most of) the world according to natural laws and psychology cannot really do that.  I can't find a fundamental theory of psychology the way I can evolution in biology and gravity in physics. I certainly understand there are mysteries in those fields that those theories cannot explain but they explain the world as we know it; I am not too concerned with the Higgs boson when I go home at night but I know jumping off a cliff is bad.

Dave Nussbaum, Adjunct Assistant Professor of Behavioral Science at the University of Chicago, is as insightful and impartial about psychology as you are going to find in a psychology insider.  He sees the flaws and he sees the solid work being done.  For some reason, the critiques of social sciences by the people outside science did not seem to bother him enough to write a response but a biologist being critical did.  He used terms like 'absurd' and 'misinformed' and 'ignorance' and then does a decent job of making the case for psychology as important - certainly better than Wilson, with his business about stererotype threat and how to rig a jury for a court case;
Psychology uses scientific methods to help us better understand and predict things about the world. To me that makes it a science. Not a perfect science — Wilson acknowledged this too — but then again the “hard” sciences got a few centuries of head start.
Well, what can psychology help us predict about that world from a science sense?  I certainly agree that from an applied sense, like marketing, it can tell us that within a range of error, X people will buy more of something if you put it in the center of a display.  But does that mean the display people in a supermarket are scientists?

Berezow believes attempts to broaden the net to include social sciences instead looks somewhat like another flavor of relativism.
But to claim it is "science" is inaccurate. Actually, it's worse than that. It's an attempt to redefine science. Science, redefined, is no longer the empirical analysis of the natural world; instead, it is any topic that sprinkles a few numbers around. This is dangerous because, under such a loose definition, anything can qualify as science. And when anything qualifies as science, science can no longer claim to have a unique grasp on secular truth.
It's a fine point. It's hard to be critical of the public when it picks its definitions of science a la carte if we let academics do the same thing.  We already have cultural  'scientization of politics', where people rationalize their agendas with cherry-picked data and those like-minded voters are rationalized by fellow politicos as everything but anti-science (anti-corporation, morality, whatever) if they don't accept vaccines or food science or climate science.

I wrote Dr. Mark Changizi, who has been in both the hard and the soft sciences, in academia and the corporate world, to get his take. He replied
The smartest experiments EVER are, in my experience, found in psychology. Cleverness is at a premium, in finding ingenious ways to control for seemingly uncontrollable things.
I *have* complained in my writing that, although psychology is filled with lots of brilliant experiments (and, like any field, a bunch of bad ones), the interpretations of them are often ambiguous. ...which is what makes cognitive science / psychology / neuroscience enjoyable -- the furniture is easier to move around. Not because it's not science, but because it's hard -- as in "difficult to conquer" -- science. Theory is much more difficult, because it's so damned complicated.
Which is terrific insight.  With all of the parameters Berezow laid out, scientists at least have a roadmap to follow.  In psychology, a lot more parts are moving because they are forbidden ethically and legally from being more laboratory-like.   If you want to read more on Changizi's insights, check out How To Put Art And Brain Together in his column here on Science 2.0.

I don't believe it is as cut and dried as Berezow laid out - we just had a Higgs particle discovery that did not have four of those five criteria in 1964 and it's difficult to claim those physicists were not scientists.  But claiming the entire science world are 'bullies' if it hurts the feelings of psychologists by lumping them in with the humanities, as Wilson did, is not really very convincing because it appeals to emotion rather than evidence. Which is a very social science thing to do.