Observation, experimentation, inference, and hypothesis

This has been an interesting day for many reasons. One of the reasons was that my friends, Krishnan and Yogesh, and I had an interesting conversation around the concept called observations. We talked about Law of Thermodynamics, entropy in closed systems, and so on. If our universe were to be a closed system, then eventually every particle in it must become either equally cold or equally hot -- this is a current thought. This was an interesting revelation for me. But, I had a doubt. How do we know that we are in a universe and that it is closed? The general feeling within us is that that may be the collective observation of humanity for 500 years or so.

I continued by saying that I believe that science is about statements on observations or possible observations. I boldly went a step further and asserted that science is not about statements on unobservables -- things that cannot be perceived or that are never cognizable to humans. To this, Yogesh, suggested an interesting conversation that he had with another friend of ours, who was not present during this conversation. His name is Shekar. Shekar is supposed to have said that it is incorrect to say that no matter can travel at a speed greater than light. The correct statement -- according to Shekar -- would be that matter cannot travel faster than light and still be observable. Yogesh feels that the term observation may not be a clear term in science and modern society and that this may be the reason why Shekar's version of correct statement used the world "observable."

This conversation was interesting because we are now contemplating on things beyond observation and on observation itself. In other words, we are operating in complete darkness using senses. So I started searching and reading about observation from the following two articles. I liked the first article than the second because it was more embodied -- it brought the observer into the conversation as an equal entity to the observed and the observation.
http://www.psych.nyu.edu/pelli/pubs/pelli2005turrell.pdf
http://plato.stanford.edu/entries/science-theory-observation/
I liked the following quotation from the first article.

The goal of this class is for the students to learn what science is by
doing it. For this purpose it is no good doing canned experiments,
demonstrating what we already know. We must explore a topic that is
not well understood, to formulate and answer new questions.

While reading the article, Krishnan came back to me and shared the article at the following URL and claimed that it provide a new insight into why humans crave for sweet food: http://www.sciencenetlinks.com/sci_update.php?DocID=349.
The article described an experiment in a laboratory on lab mice -- both genetically engineered and naturally existing. The following are statements from the experiment.

1. Mice naturally prefer sugar-sweetened water to plain water. 
2. Genetically engineered mice that could not taste sweetness preferred sugar-sweetened water over plain water and artificially sweetened water. 
3. Sugar intake is known to increase dopamine levels in brain. More dopamine is sensed as a good state. 
4. So, the reason why mice (and, therefore, humans!) prefer sugar is because the brain likes it!

I tried reasoning with Krishnan about the validity of the above four statements when at one point he informed me that the study was performed by reputed scientists. I informed him that I really do not mind the reputation of the people who conducted the experiment but only about the statements emanating from it.

I said that my problem with Statement 4 is that it makes unwarranted leaps towards inference. I would liked to see statements on the behavior about another class of genetically modified mice: (a) mice without ability to taste sweetness and dopamine saturated; (b) mice without ability to taste sweetness and dopamine unsaturated; (c) mice with ability to taste sweetness and dopamine saturated; and (d) mice with ability to taste sweetness and dopamine unsaturated. The implicit assumption behind this experiment is that dopamine saturated mice would not detect any change in dopamine due to intake of sugar. Without observations from experiments (a), (b), (c) and (d), it is difficult to say that increased dopamine may be the reason for craving sugar by mice.

Further more, even if it were to be shown that increase in dopamine is the only reason for craving for sugar by mice, there is no reason to believe why that should be true for humans as well. Unless, of course, we wish to perform a similar experiment on humans, if our natural laws permit!

At this stage, Krishnan quipped that the article should not be dissected like we did but only read, accepted, and get a kick out of the suggested hypothesis. At this stage, I realized that science is but a part of a greater activity that preoccupies modern society and its humans -- entertainment. Our universities, scientists, administrators, students, and everybody exist but for one reason -- to amuse us!

The previous statement is meant to be for amusement -- so please do not dissect it! :-)