Historically 'science' has been seen as the study of the 'nature' of things. Psychology has everything to do with the nature of people, and so, providing we consider ourselves manifest, we are also things :)
Therefore yes, undoubtedly psychology is a science. There are several systems of study in the area or psychology, a great body of knowledge has been amassed, and this is 'the science' of psychology.
What has always been in question for psychology is 'which system' you study as to whether or not you are following scientific principles or not. e.g, a Freudian, might argue the science of Jung, and vice verca.
A good example of scientific distinction might be, the difference between an astrologer and an astrophysicist - both regard the heavenly bodies, but one based upon supposition and the other based on experiment and applied knowledge of physics.
The question would be more whether or not your study and experiment was measurable, repeatable and applicable.
Happy new year :)
Hello @shelbi, thank you so much for taking the time to comment! :D
Funny you should mention Freud and Jung, in my opinion their approach was not very scientific at all. In fact I believe that part of the disbelief in the scientific nature of psychology stems precisely from the theoretical and subjective methods of psychoanalyses, the one psychological therapeutic method (among many) that the general public still seem to see as a synonym for psychology; well other than self-helfp!
So, yes, when you address psychology as in 'systems' you could argue that classic psychoanalyses might be the least scientific one in its methods. However, one shouldn't forget the many case studies Freud himself conducted not only with his patients but with himself, which definitely brings the systematic aspect of science to his field.
Finally, an experiment which cannot have its variables measured it is a badly designed experiment, there is no point in designing an experiment that can not be measured as there would be no findings. On that same note, whether an experiment can be replicated or not is mainly to do with how well the methods have been reported by the researcher and not how scientific it is!
Happy New Year :)
Yes Freud was a great one for therapeutic practice, and very diligent. I would say that psychology is completely measurable - or at least the results of therapy are, which I guess is what your saying. Just because we cant physically cut it up and put it under a microscope, doesn't make a result any the less 'data', and if the data or result occurs each time, then you do have a measurable repeatable experiment. I suppose all the arguments come in when we try to interpret that data. Both freud, and Jung, could carry out the same experiment or therapy, exactly to the letter, but I'm sure each would interpret the data differently. Its no different in the hard sciences, such as Mathematics or Liquid dynamics - all will give you data to play with, what people make of that data is really what is in question, and even in these other sciences, there is always much dispute amongst the different institutes and organisations as to what the data represents. Psychology, is a branch of what we call the social sciences, we might argue its pro's, con's and method, but it is a science never the less - after all, science is the work and collection of data, its not the hypotheses that follows. Sorry that was a long reply Oo