My mind goes probabilistic

In my immediately preceding post I ventured to offer a probability based approach to choosing from a mound/basket of vegetables at the grocery store. That was a certified layman way of understanding sampling techniques. Once I have put my foot in the mouth, I cannot stop myself. I am shoving it down further.

Here, I offer uncertified proof for how our evolution equipped our mind to think probabilistically. The first scenario is this: You are standing at the curb in a relatively desolate stretch of the road and want to cross the road. At some distance, neither too far nor too near, you see a two-wheeler coming down the road at good speed. Yet, you cross the road ahead of the vehicle.

The second scenario matches the first one as closely as possible, but for one difference: The vehicle this time is a big truck. I speculate that you would think twice before stepping onto the pavement and that delay is likely to have stopped you from crossing the road in front of the vehicle. My conjecture is evolution has prepared you to evaluate the probability of being driven over and, more importantly asses the consequence of the chosen action. An encounter with the two-wheeler is likely to have been a far less dangerous affair.

I know, you say, ”I know nothing of probability.” Neither do I.

But, we are not alone. It was at a physics conference soon after WWII someone dared mentioning that bats navigate dark caves through echo-location. This is basically how radar works. You send out a signal, receive its echo bouncing off an object, estimate the distance and it is bombs-away after that. Quite complicated calculations it involves. So, the presenter was asked, “Buddy, does a bat have the brain power – its brain is so small, in case you did not know – to do the sophisticated math that one needs for echo-location? Ha …”

Bats need not do the kind of high math we have to do to get echo-location working for them. They must have developed (and it has been proven that they have) some other effective way of doing what we call echo-location  to evade the predator or pounce on the prey. Otherwise the species could not have survived. I am sure bats do not identify or call what they do as echo-location. The secret is all in evolution.

Now, what is good for bats is definitely good for human beings. We do not do probability while crossing the road. But – and this is the point – what we have been imbued with by evolution over millions of years is explainable by math that we have evolved to develop, understand and apply to recognize our own actions. You, of course, recognize the circularity. In some sense, I believe this is the consequence of our ability to think about ourselves, being self-aware. 

We ask ourselves, almost ceaselessly, “Why do we do this? How did I do that?” We may not end up with the correct answer, but for whatever reasons we know we can make a model of our behavior to some level of validity. This “some level” is what makes our thinking probabilistic. We are never sure. And, probability helps moderate that ignorance.

I did warn you in the title that I am going probabilistic. But, you think that I have gone ballistic, off to the outer orbits of sanity. You are probably right. But, as you can see, I am still surviving.

Raghuram Ekambaram