The difference between amps and speakers

Speakers make sound, amps make speakers sound. I know, the distinction is perhaps obvious but it occurred to me this morning the differences between devices that generate acoustic waves in our homes and boxes that use electrical waves to power them are more complex than at first glance. Obviously a loudspeaker is very different than a power amplifier. A loudspeaker is mechanical in nature; it has electrical properties that animate its mechanics. A power amplifier is electrical; we cannot hear or see what goes in or out. Yet, as consumers we are asked to make choices based on nothing more than the reviews we read and the sounds we hear. And while we can hear sounds from a speaker, we cannot use the same mechanism to judge an amp. Every piece of electronics in our chain is decided upon through the lens of a loudspeaker and thus colored and confused by the same. We never truly hear an amplifier, just as none of us has ever truly seen the surface of Mars; it's always colored by a telescope or camera. It's instructive to remember that which we hear in our listening environments is always colored by the lens of loudspeakers, and none are neutral.