The first duty of the sovereign， that of protecting the society from the violence and invasion of other independent societies， can be performed only by means of a military force.
如果物体处于静止状态或作匀速直线运动，只要没有外力作用，物体将保持静止状态或匀速直线运动状态。
要真正理解宇宙，我们必须首先理解我们理解的极限。
Architecture is a social art.
