A physicist's educated intuition indicates that the presence of some readily analyzed forces in a gas reduces one's uncertainty about the actual state of affairs at the molecular level below the corresponding uncertainty in the absence of such forces. There ought to be a connection with at least one of the entropylike expressions appearing in statistical mechanics. A simple proof is given that, in the classical limit, the presence of any forces (represented by potentials dependent on particle positions only) does reduce the Gibbs entropy below its value, at the same temperature, in the absence of such forces. This may be taken as support for an interpretation of the Gibbs entropy as a measure of one's uncertainty about the actual microscopic situation, given the information typically available.