I say that negativism is an underappreciated part of the creative thinker's bag of tricks. I begin my defense of negativism by noting the strange asymmetry that nature has created in the learning process of living organisms. Consider genetics as a learning system. Here we have a species living in a constantly changing environment. At the genetic level, the creation of responses to environmental change is a random process.
Viruses can mess up the code.
These are for all genetic purposes essentially random processes. While the creation of new genetic ideas may be random, the evaluation of these ideas is most certainly not random. An organism born with five legs or longer ears or shaggier fur will have to compete in a brutal environment. This is what my friends would call an overly negative approach to problem-solving. What bothers most people about this process is its lack of balance.