David judges the joint occurrence of two uncertain events as being more likely than the occurrence of either of the events. david is

Displaying the conjunction fallacy.

The conjunction fallacy happens when it is assumed that two events are more likely to happen together than the occurrence of either one of the events.

A common, useful example is the following:

Linda is 31 years old, single, outspoken, and very bright. She majored in philosophy. As a student, she was deeply concerned with issues of discrimination and social justice, and also participated in anti-nuclear demonstrations.

Which is more probable?

1. Linda is a bank teller.

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

Although most people choose 2, the probability of two events occurring together is always less or equal to that of either one occurring alone.

they all focused on themes about the inevitability of death.