But how do you start without the first set of friends and, so to speak, the base case of the induction fails?

I have a hard time believing anybody starts from absolute zero in these scenarios, but here's an example from a self-proclaimed introvert:

- Pair up with random guy at a school hackathon because we're both without a project (+1). Meet a friend of his (+1).

- Meet him months later for birthday drinks. Introduced to his friend, we end up starting a band with 3 of his friends. (+4)

- Meet countless people through the music scene (+?)

- Go to another hackathon together with first guy, join another pair (+2), win, catch a recruiter's (+1) attention and get an internship.

- Meet countless people over the summer during the internship (+?)

- [...]

That's the very short version. Most of my network can be traced back to like, 4 people that started as strangers. There were a lot of dead-ends initially, sure. But it really does just take one person to build or reshape your entire social circle, change your career, etc. The first set is the hardest imo, but there's no excuse* for not going out and trying to find it.

*excepting, of course, any affliction which might make social interaction difficult. "i'd rather stay home" is not an afflication

It's much easier in a college setting. Much easier.

I've now moved a couple of times in my adult life. I find that it takes about six months to find a group of people to hang out with occasionally, and two years to acquire a small group of friends that I feel comfortable with. It seems to get harder as you get older, too.

This works but it takes years

Get some hobbies that involve interacting with people. Or go to meetups about your hobbies.

In my experience (30+), the truly differentiating factor is the nature of your interests outside of work, your energy level. I like to think of it as optimising your contact surface.

If your interests are not of a social nature, maybe try something that is. I climb a ton and that sport has resulted in so many new and valuable friendships I couldn't even list them here. Also, figure out who you jive with at work, if they have time to hang out and if there are overlapping interests. Invite colleagues to lunch.

Making friends take energy, it is like dating really, where you attempt to determine if there's a match. It might involve getting a beer or doing activities and generally being outside of ones comfort zone. You'll either fail or you'll get to a point where you can both relax comfortably. But it is going to be work for a while.

Personal anecdote:

I was in NY for 3 months for work and my luck was that my primary hobby, climbing, is a very social activity and walking up to strangers is sort of welcomed. I spent the first month never turning down an invitation from colleagues and making an effort of talking to people at the gym. The first month was rather gruelling, and I sometimes felt like I was intruding on people's good will and perhaps their pity of me being alone in a new city. But after the initial brutality, my coworkers became comfortable around me and started inviting me to things they went to and I became a part of a small group of regulars at the climbing gym. I made a bunch of friends for life and I miss them dearly now that I am back again.

Find some activity you're interested in and go do stuff. Attend a convention, go to a concert, take a class, join a club, volunteer for an event or a cause. Meeting people who share one or more of your interests or passions is an excellent way to grow your friend group. It's actually shockingly easy to meet people if you're even a little active and willing to put forth some effort.

Register for a social Hobby. Karate, guitar, dancing, book club or frisbee. I wouldnt reccomend a gym, though maybe on the side for health reasons.

Yes, I've found Meetup to be very useful in finding like-minded, social people. More difficult to make close friends, but significantly expands your ability to do so.

Very true. Meeting friends through friends is much more effective. And Networking events usually wind up having too many insurance salespeople!

Thats a catch 22 for some. Cant meet friends through friends if you dont have feiends.

Just think about it as an exponential function. All you need is a seed value of 1 -- so make that one friend.

Not really - it only works if that one friend is connected, and if they are willing to take you to events with their other friends. I know many people who prefer meeting 1-on-1.

Has to be the right friends and social activities too.

I don't want to drink or do other recreational drugs (even if they are legal). Going and not doing also seems to be not an option, you're clearly the black sheep.

I don't drink often, and when I do it's usually just one or two with my partner to unwind at home. I used to though, pretty heavily, and making that transition was tough: a) I definitely had been using alcohol as a social crutch and felt super self-conscious at parties when I wasn't drinking, and b) a lot of my friends knew me as a drinker and would give me some grief about it.

I've found two things that really made it easy to go to parties and things and not drink:

- Don't make a big deal about it, just politely decline when someone offers you a drink. "Can I get you a drink?" "I'm good, thanks" or "no thanks" is all it takes. If you say "no, I don't drink" to someone who's been drinking, that's way more likely to turn into an awkward situation. Alternatively, "I've got to drive" works too.

- Don't make it obvious that you haven't been drinking. If people are cheering and being loud, participate! You're at a party! When I first cut back, I often tried to talk about whatever it was I was thinking about at the time and was often met with "Dude, why are you thinking about that right now? We're on a pub crawl!" Time and place.

Now when I go out to a party, I'll hang out, do whatever's going on, and usually offer a few people a ride home whenever I'm getting ready to leave. Still gives me a chance to socialize for a while, catch up with old friends/meet new ones, and then I get to wake up and feel great the next morning.

Edit: re: being the "black sheep"... if you're otherwise just going with the flow of conversation and energy in the room, the only person who will really notice whether or not you're drinking is you. Hell, I sometimes even play drinking games (e.g. sociables) with a glass of water. Some people know that I'm just drinking water, some don't, but no one cares because I'm in there having fun with everyone else.

Also, if you're at a party with red solo cups, water is pretty much indistinguishable from any other drink, and if you're really feeling self-conscious about it, some Sprite or Coke or whatever with a few ice cubes is visually identical to a mixed drink. Beer might be trickier.

There are lots of non-drinking non-drugs activities out there. In any major city, there are others with similar interest. Jiu jitsu, swing dancing, Minecraft, legos, take your pick...