Monthly Archives: September 2011

Diff Tools

My favorite diff tool is FileMerge, one of Apple’s developer tools, which can be accessed from the command line as opendiff.

But from the command line, my (next most) favorite diff tool is colordiff. It’s called that because it color-codes the output when it’s used interactively, making it IMHO easier to see what’s changed. Actually, colordiff is just a wrapper around the real diff tool.

Another nice tool is dwdiff, which is compares two documents and highlights the different words rather than the different lines. So does wdiff.

(Back to my list of Unixy tools for the Mac.)

Intelligence and Disease

Why are some places more blessed with smart people? (Yes, I assume that more smarter people is better for a society, and no, I won’t attempt to convince you.) Some recent studies suggest that disease may be the reason for uneven distribution of intelligence:

In our 2010 study, we not only found a very strong relationship between levels of infectious disease and IQ, but controlling for the effects of education, national wealth, temperature, and distance from sub-Saharan Africa, infectious disease emerged as the best predictor of the bunch. A recent study by Christopher Hassall and Thomas Sherratt repeated our analysis using more sophisticated statistical methods, and concluded that infectious disease may be the only really important predictor of average national IQ.

The researchers wondered if, since infant humans spend as much as 90 percent of their calories building and growing their brains, fighting disease detracts from that important work.

If this finding is correct, then the uneven distribution of intelligence may be a developmental matter rather than genetics or uncontrollable environmental factors like climate.