There's a bit of a litmus test you can apply to belief systems to find out if they're definitely objective.
An intelligent alien species that's never met humans would almost certainly invent math. The syntax and organization would probably be different, but the rules would be the same.
On the other hand, aliens would almost certainly not write The Hobbit.
I don't know, it may be the current intellectual culture's speciesism that we often think that. For instance, they may have many modes of perception better than math. Or even if they have a "math" sense that's oddly like ours, they may be unaware of it because it's unconscious... in their underlying circuitry... just like we're not built to directly introspect many of our own capacities.
We may even be in constant contact with "aliens" now, but unable to perceive them meaningfully. Like most lifeforms maybe couldn't tell us apart from a rock or rubber.
An intelligent alien species that's never met humans would almost certainly invent math. The syntax and organization would probably be different, but the rules would be the same.
On the other hand, aliens would almost certainly not write The Hobbit.