So it does have clocks and counters though right, and not just some passive or active filter
The internal circuit can be assumed to be an AC-coupled light amplifier, followed by a diode and capacitor performing demodulation like a simple AM receiver, and an output transistor with on-off output. There is a filtering action, so that extremely short bursts will not be output, but even if some slightly longer bursts make it through, the external circuitry (e.g. logic, microcontroller) can usually clean further since in a system, usually a protocol like RC-5, SIRC, etc is used.
There's more to it in terms of sophistication, as can be seen in the datasheet block diagram, but in a nutshell, even a black-box assumption is sufficient to work with it, namely, that it simply removes the carrier frequency from the infra-red signal, and isn't so fast-responding that it will output the shortest of bursts . No other logic, state-machine or otherwise, is inside there.
The easiest way to see what is going on, is simply apply power to it, and look at the output using an LED (connect the LED cathode to the output, and the anode to +ve), if not a 'scope. You may rarely see the occasional flicker on the LED, that's some ambient burst of flickering light level (or, possibly more likely, some electrical noise very close by) making it's way through the AC-coupled amplifier, but you won't see the LED turn on much unless a real burst is sent (from a remote control, or a 555 attached to an LED, etc).
In a normal home environment, you probably won't see the LED visually flicker at all, the output is very clean. You'll only see the LED turn on in a sustained way when using the 555+LED or normal remote control.