Saying no
Paul Graham's essay The Acceleration of Addictiveness points out that the internet, when used to procrastinate, is a waste of time enjoyable enough and dangerous enough to be compared to addictive drugs like heroin or cocaine.
What should you avoid doing, because it feels good despite having no tangible benefit? The obvious ones are easy: drugs like methamphetamine, heroin, and cocaine, which directly mess with your brain chemistry to make you feel good. Similar problem substances include opium, LSD, MDMA, alcohol, nicotine, marijuana, and caffeine. You may disagree about some of the milder ones, but they're all mind-altering drugs in some way, and all of them cause dependency problems and health issues, and provide minimal (if any) benefit.
Less obvious are things in the too-much-of-a-good-thing category, like over-eating. Food is an absolute necessity, but, as Graham mentions, our relatively recent ability to grow and produce highly nutritious and calorie-rich food has led to a need for us to actively suppress our food cravings.
The waste-of-time category overlaps quite a bit with the too-much-of-a-good-thing category. It includes such things as stories and fictional entertainment of all sorts (books, television, movies, comics, theater), games (board games, card games, and, especially, computer games), and music (including attending concerts as well as listening to your MP3 collection). Opera combines music and theater. Watching sports, as distinguished from playing sports, is a waste of time. Pornography is a real waste of time that could better be spent trying to get the real thing.
Reading stories and news on the internet can teach you things (much like reading fiction), but unless you're extremely selective in your choice of what to read, there are much more efficient ways to learn things. Daily news doesn't give reporters enough time to go into the depth needed to really learn anything about any one area before the story has to be written, so very little "news" actually contains anything new. Like entertainment, the news often focuses on things that cause strong emotional reactions, rather than things which have a tangible effect on your life. (News stories are often about things which have a tangible effect on someone's life, just not yours.)
I suppose all that makes me sound like a guy who never has any fun. But all I'm really trying to say is that some types of fun are bad for you.
What should you avoid doing, because it feels good despite having no tangible benefit? The obvious ones are easy: drugs like methamphetamine, heroin, and cocaine, which directly mess with your brain chemistry to make you feel good. Similar problem substances include opium, LSD, MDMA, alcohol, nicotine, marijuana, and caffeine. You may disagree about some of the milder ones, but they're all mind-altering drugs in some way, and all of them cause dependency problems and health issues, and provide minimal (if any) benefit.
Less obvious are things in the too-much-of-a-good-thing category, like over-eating. Food is an absolute necessity, but, as Graham mentions, our relatively recent ability to grow and produce highly nutritious and calorie-rich food has led to a need for us to actively suppress our food cravings.
The waste-of-time category overlaps quite a bit with the too-much-of-a-good-thing category. It includes such things as stories and fictional entertainment of all sorts (books, television, movies, comics, theater), games (board games, card games, and, especially, computer games), and music (including attending concerts as well as listening to your MP3 collection). Opera combines music and theater. Watching sports, as distinguished from playing sports, is a waste of time. Pornography is a real waste of time that could better be spent trying to get the real thing.
Reading stories and news on the internet can teach you things (much like reading fiction), but unless you're extremely selective in your choice of what to read, there are much more efficient ways to learn things. Daily news doesn't give reporters enough time to go into the depth needed to really learn anything about any one area before the story has to be written, so very little "news" actually contains anything new. Like entertainment, the news often focuses on things that cause strong emotional reactions, rather than things which have a tangible effect on your life. (News stories are often about things which have a tangible effect on someone's life, just not yours.)
I suppose all that makes me sound like a guy who never has any fun. But all I'm really trying to say is that some types of fun are bad for you.