Wrote this ages ago, maybe in 2003. Not sure if I would now characterize mutable signs as “detached” though as that implies emotional detachment. It’s more like a lack of attachments.
While much has been written about sign elements (which are easily related to other systems such as psychological typology, tarot suit etc), I found in my early studies that modality was often overlooked. Here is a more in depth examination of sign modality, also known as quality.
There are three modalities which can basically be summed up as beginnings (cardinal), middles (fixed) and ends (mutable). Each group has its own particular characteristics and it is well worth noting when interpreting a chart if there is a bias towards a modality, or lack of one.