The decision-making process, the tug between emotion and reason

Emotion and reason collaborate to help us take decisions in our lives, from the color of our shirt, to the choice of our partner.
If decisions were based on reason alone, we would freeze and panic. We will be overwhelmed by the sheer amount of choices and data that we would have to take into account even for the simplest of decisions.
To be able to choose between two bags of potato chips, a decision based solely on reason would take us weeks, even months before we could reach any conclusive decision.
The data is almost endless. The amount of salt, the quality of the oil, the effectiveness of the packaging in preserving the taste and crunchiness of the chips, the interactions between the ingredients, and the list goes on and on.

For many cases, we gather data, ask around, investigate, then at the end, we make a decision based on a gut feeling, intuition or our neighbor's choice. 

Logic and conscious thinking has obvious limitations, it can't deal with the sheer amounts of data required for the slightest and simplest of decisions.

We take shortcuts, most of them unconscious, and we rationalize our choices after the fact through logical, conscious contortions.