On The Linda Question

This week’s book learning is from ‘Thinking, Fast and Slow’ by Daniel Kahneman –

“Linda is thirty-one years old, single, outspoken, and very bright. She majored in philosophy. As as student, she was deeply concerned with issues of discrimination and social justice, and also participated in antinuclear demonstrations.”

Which alternative is more probable?

1. Linda is a bank teller.

2. Linda is a bank teller and is active in the feminist movement.

When posed with this question and asked to answer, 85% of Stanford Graduate Business School students, all of whom had taken several advanced courses in probability, statistics, and decision theory, along with about 85% to 90% of undergraduates at several major universities chose option 2.

Think about it for a moment though: Every feminist bank teller is a bank teller! Picking Number 2 nearly violates the basic laws of logic, not to mention probability. Yet nearly everyone failed. Why?

Daniel Kahneman points out that we have 2 processing systems – the intuitive and quick to respond

System 1 that ‘thinks fast’ and the more lazy, calculative and deliberate System 2 that ‘thinks slow’.

The point Kahneman makes here is that we often jump to conclusions on many problems without thinking ‘twice’ i.e. engaging our system 2.

I found this insight fascinating.. And more learnings to follow on the 2 systems..

Here’s to observing our 2 systems in action this week!

PS: Apologies to feed readers who are seeing this twice. Some posting issues!