obvious, oblivious

Obvious or obvious means easily noticed, seen, or recognized, literally or figuratively--
Look for the house with the large pine tree; it's obvious, even when driving by.
The answer should be obvious to anyone who did the assignment.
The reason for his dismissal was obvious; he missed too much work.
Don't stare; you're being too obvious.

Oblivious or oblivious means unaware; unmindful; lacking memory--
He seems oblivious to the noise the kids are making; doesn't it bother him?
He woke up oblivious of where he had been the night before.

Now that you know that, you can say--
"He seems oblivious to the effects of his behavior, no matter how obvious we make our disapproval."