How much is that some that you can lose? Only you can answer on how much you're willing to invest, if it's 60% then that's it. Risk appetite of each of us changes based on the circumstances that we're facing. You may say that you're okay with that percentage for now but it could change tomorrow if some unexpected things happen and vice versa.
If you think you will lose by investing in Bitcoin then I think you should not invest.
He's willing to lose and understands that there's risk upon investing but IMHO that doesn't what he means to say that he'd definitely lose.