I always thought you would need the IR before you could get a night rating
No - you still fly by looking out the window. You need to appreciate that there are times when you won't be able to see a horizon, or where visual illusions can make you fix on a false horizon, and therefore rely much more on your instruments.... but not to the point of relying on them in the way that the IR teaches you to fly.
There are many people who advocate requiring an IMC rating or IR before you're allowed to get a night qualification. But on the other hand, in many countries (e.g. the USA) the basic PPL includes night-flying privileges and you don't hear of PPLs crashing all over the place because they tried to fly at night in the US. You would certainly want to exercise some caution about where you fly if you don't have any instrument training, though - flight over unpopulated countryside or over the ocean at night, on a moonless night, for example, would be a bad idea.
FFF
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