It is worth noting that "political science" covers a lot of ground... Much like economics, there are some sub-fields that deal with "small" questions with a great deal of empirical rigor and and other sub-fields that are more theoretical and philosophical. The closer the sub-field is to stats & neuro-physio/psychology the more it resembles other hard sciences. The past decade has seen a lot of interesting work in this area and a lot of it has turned out to be something of a surprise in terms of deflating the "rational actors making reasoned choices" myths that many people subscribe to.
