“The phrase ‘necessary and sufficient’ blamed for flawed neuroscience”
“The logic of the term is at the heart of the dispute. It’s too often used as shorthand to mean ‘linked to’ or ‘important for’, the authors say. And this sloppy use, they argue, can lead scientists in the wrong direction, especially in genetics.
If a gene is necessary and sufficient for something (as often claimed), strict logic demands that that gene alone can do the job. For example, the gene eyeless is certainly necessary for a retina to develop. But it is not sufficient — if it were, then logic would demand that ‘if eyeless exists, then a retina will develop’. This is false; other genes and factors are needed as well. Yet eyeless is often described as being necessary and sufficient for retinal development.”
This is so validating, I have noticed the use of this term and been skeptical but assumed that I was missing something. I would go back over the concept of sufficiency, try to twist it to match what the authors were saying… It just seemed impossible that someone would use the phrase wrong.
