Well....having spent a good amount of time in some very hot and very humid climates - you quickly learn the value of eliminating opportunity for discomfort in any way that you can. Especially when that discomfort could lead to slowing you down or even de-habilitating physical conditions.
I do not even wear cotton. Not even cotton socks. The reason cotton makes a great bath towel to the same reason that it makes for a very poor choice next to your skin.
If you will wear a "smart wool" blend of 70% merino wool ( softer than cotton - dont let the word "wool" fool you ) and nylon or poly propylene - you can wear really thick sock in the summer - and your feet wil remain cooler and drier than ever before. And healthier.