Do you know how many times you use “Probably” in a day? The word refers to the possibility of a certain event happening. Irrespective of our ability to calculate the probability, we frequently estimate, compare and make decisions based on probability. It is a subjective degree of belief in the occurrence of an event. The concept of probability has philosophical, psychological and scientific interpretations. Putting simply, the probability of an event is the ratio between the number of favorable events and the number of all equally possible cases.

Evolution of probability theory

Initially, probability theory was inspired by games of chance in the 17th century. However, its complete axiomatization had to wait until Kolmogorov’s ‘Foundations of the Theory of Probability’ in 1933. Over time, probability theory found several models in nature and became a branch of mathematics with a growing number of applications. In physics, probability theory became an important tool in Thermodynamics and Quantum Physics.

Probability is the reason why a vast majority of phenomena from nature and society are considered stochastic (random). Their study cannot be deterministic. Probability theory deals with the laws of evolution of random phenomena. Rolling a die, tossing a coin pushed us to focus on prediction taking us away from the initial relative ratio proportion of probability.

The distraction towards random elements was owing to the details like the initial impulse of the die, the die’s position at the start, characteristics of the surface on which the die is rolled, and so on. A drunkard reaching home, the time it takes him to travel a fixed distance varies because of random elements (traffic, meteorological conditions, amount of alcohol, etc). These were the details which forced us to assume that the essential conditions of each experiment are unchanged (Ceteris paribus).

This focus on prediction and cause and effect took us to develop experiments and its results and focus on developing methods to study random phenomena. This was despite the fact that an equal aspect of probability is about relative frequency. How many times you may repeat an experiment in identical conditions, the relative frequency of a certain result (the ratio between the number of experiments having one particular result and the total number of experiments) is about the same.

Event focus, the evolution of phenomenon, quantity focus and conditions focus complicated this further. Probability is not the expression of the subjective level of man’s trust in the occurrence of the event, but the objective characterization of the relationship between conditions and events, or between cause and effect. The probability of an event makes sense as long as the set of conditions is left unchanged. Any change in these conditions changes the probability and consequently the statistical laws governing the phenomenon. So, if the initial conditions can never stay constant can science ever find a solution?

This is why the notion of a butterfly ruling our life, the idea that long-term predictions are impossible to make. Will our life remain random? And will we ever come out of this quandary that even though systems are deterministic, meaning that their future dynamics are fully determined by their initial conditions, with no random elements involved, they are still chaotic? Isn’t it strange living this deterministic chaos?

We want to believe life is random through the same random theories talk about relative proportion and patterns. We want to develop theories of randomness though we have a scientific history of predictability and order in physics. The drunkard’s behavior has an order, but we don't consider it one. Human beings have problems with extremes. If there is an extreme mankind can't explain, we get into thoughts of disorder, unpredictability, lack of equilibrium and inefficiency. The very fact that a market crisis is a case of inefficiency for us, while earthquakes are natural predictable disasters also shows our double standards in our treatment of extremes. We built economics around normalcy and when Mandelbrot proved that extremes were normal our whole world of order seems to have collapsed.