Mixtures and pure substances
The theory of fluid intelligence is based on the distinction between the fluid and crystal intelligences. The crystal intelligence is based on the knowledge that one has already and the the fluid intelligence is the intelligence to respond to future and unpredictable challenges.
I think that this distinction is very fitting and that the fluid intelligence was probably the one that drove human evolution; and perhaps is the more relevant of the intelligences.
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The correct answer is Learned Optimism.
Martin Seligman developed an area of psychology known as Positive Psychology. One aspect of positive psychology is learned optimism. It is where you teach yourself to think positively instead of negatively, you use certain techniques to alter your thought and behavior patterns so you see optimism in life instead of pessimism.
