After reading Act II and hearing the opinion of several characters(Ophelia, Polonius, Claudius, etc.) Is Hamlet truly a prince gone mad with grief?

After reading Act II and hearing the opinion of several characters(Ophelia, Polonius, Claudius, etc.) on Hamlet’s mental state, what do you think? Is Hamlet truly a prince gone mad with grief? Is it all an act to trick his loved ones? Or does the truth lie somewhere in between? Use quotes and show how you interpret his actio