what do you reckon?

I've never understood the term 'cold hearted' for people. Aren't hearts warm? Because they aren't cold. Blood in our body is warm, and the heart is what pumps this blood, so because in society, this term means to be 'rude, self-scented, disrespectful, unthoughtful, or something along those lines', I don't think it's a good term to use.