Anyone who studies history quickly discovers that ideas don't come cheaply and they don't win easily. There are almost always deep divides and passionate camps surrounding big ideas, and the ensuing battles are some of the most interesting artifacts of the past. Shown are Neils Bohr and Albert Einstein, who began a debate on quantum indeterminism.
The arguments revolved around what is known as the measurement problem and whether or not particles in the quantum state were really both wave and particle at the same time until measurements were made. Einstein wanted to insist that the apparent indeterminacy at the quantum level was just a (temporary) inability to measure certain properties, while Bohr maintained the impossibility of determining precise values of certain properties because at the quantum level the values were by nature uncertain.
http://www.onlinecourses.org/2009/03/10/the-10-biggest-intellectual-fights-of-all-time/
From the Upcoming ueue, submitted by greeneagle.