That's entirely up to you. You are considered an adult who has reached the age of consent...so no worries about him contributing to the delinquency of a minor. While he is older, he's not really old enough to be your father (well...unless he became a teen father...).
Some things to consider---due to the age differences, you both are at different stages of life. Sometimes one will find that each person has different wants and needs that are age related. For example, many 21 year-olds often are still learning about themselves when it comes to what you want to do with your life and what you expect your life to be in the future. Many 37 year-olds are at a point where they want to settle down (if they haven't already) and may well be more of a homebody than a 21 year-old.
Of course, this is all generalizations but still something to think about. Some 21 year-olds are very mature for their age and are ready to settle down while some 37 year-olds are still immature, unsettled and don't know what they want to do with their lives.
Certainly, many couples with similar age differences have successful long-term relationships. I think those relationships work because 1) they have common interests and values; and 2) They are both on the same page when it comes to what they want in life.
Of course, long term, the older person will start to decline physically (unless the younger one's health deteriorates) well before the younger one. Sometimes when that happens, the younger person will become frustrated when the older one can no longer keep up.
All that said, if you like this man and want to get to know him better, then go for it. Don't listen to others who are focused on the age difference. If their concerns were along the lines that he was an unsavory character, for example, then hear them out. However, if they're only saying he's too old for you---tell them that's for you---and only you---to decide.
Right now, since you're first dating, just take the time to get to know one another. You can think about the long-term picture if, and when, things become more serious.
I will leave you with one thought, however. In cases where I've heard about people with similar age differences, sometimes I will hear of the younger one saying something like this: "I met him when I was 31 and he was 47. If I had met him when I was 21 and he was 37, I don't think I would have gone out with him. I'm a different person now 10 years later, more settled and I know what I want out of life. I wasn't at that point when I was 21."
Again, something to consider. However, you know yourself best so, it's all up to you.