It’s Complicated: What Can We Know About Science?

Frustration!

My student blew out a breath. “Well, they look square to me!”

We’d been discussing the shape of the onion cells (they’re elongated). As an experienced teacher, I noticed the incorrect notation in her lab write-up and suspected that she had not actually examined the cells.

After focusing her microscope for her, I challenged the student to look again. After all, the shape of an onion cell is not difficult to ascertain, and it is not square.

What is True?

That made me ponder, what can we say is true in science?

From Math to Physics and Chemistry

In mathematics, 2+2=4 is always an accurate statement.

But, as the complexity of the science increases, going into physics and then chemistry, the “truth” becomes less obvious. For example, mixing hydrochloric acid and sodium hydroxide will produce salty water. That’s true. However, an exact description of what happens (possibly an explosion) requires consideration of the concentrations of the reagents, the temperature, the air pressure, and other factors. A simple statement no longer suffices.

From Biology to Psychology and the Like

In biology, the factors that must be considered are exponentially increased in comparison to chemistry. Essentially, biological systems are a complex mixture of chemical and electrical reactions controlled by the application of many levels of information, not to mention the environment. Predicting the outcome of changing one parameter can be almost impossible.

The complexity and thus the impossibility of drawing absolutely accurate conclusions and predicting the effect of a change in one parameter further increase as one progresses into fields such as psychology, sociology, ecology, and the like.

Possums

To illustrate this principle, consider the work of Dr. Carolyn Nersesian from the University of Sydney. This ecologist used a technique from chemistry (titration) to understand the feeding behavior of eight brushtail possums. Basically, she slowly increased the concentration of a poison in the food in a sheltered area (tree) while offering the animals untainted food in a less sheltered area that had been pre-treated with fox urine and feces.  The goal was to determine the concentration of poison that would cause the animals to risk exposure to predators by moving from the sheltered to the unsheltered area.

This is a typical approach in scientific research: one parameter is changed while all others are kept constant. The scientist then observes what happens and assumes any change is due to the parameter that they altered.

However, a bit of thought reveals that there are numerous potential confounding factors. Was the temperature in the unsheltered area different from that in the trees? Did the animals communicate, making the “decision” of one apply to all? Would the results have been different if urine from another predator had been used–or if there was no urine? The questions go on.

Science

So how does this apply to our understanding of science? Simply, we must be aware that science cannot provide absolute answers at levels much above that of mathematics. And by the time one progresses to psychology and sociology, extreme caution must be exercised in the interpretation of any data.

After all, what would it take for a person to leave the safety of their home for the pleasure of Starbucks? Judging by the lines, not much. But, if it’s cold and rainy…then titrate all you like, I’m not going out!