I know it will sound radical, but in my view we all are selfish beings, even our selfless acts are brought by a desire to reinforce a view of ourselves as selfless, or get a good feeling for being selfless, we just don't recognise it. Even love is selfish, you love someone because that particular person adds to your life, your selfless acts in life, are actually measures you're taking so that you wouldn't lose this person you value the most. All in all, we aren't particularly conscious when we do this things, but are inherent in our systems, encoded in our DNA. Excessive and blunt self love is what's considered selfishness.