No matter how much we want to believe we truly have free will, we don't.
Every decision we make is influenced by biological & economic incentives and our circumstances (physically, psychologically, environmentally, etc.).
There are thousands (millions, bajillions?) of factors pulling us in all sorts of directions we barely notice. All of these factors bias our decisions, and––if we're not careful––hijack our lives.
When we're faced with a crossroads like going to the gym or going to sleep, factors like how tired we are, how impulsive we are, how cold it is outside, how expensive the uber is, etc. influence which decision we make.
Even if we notice our impulses pushing us in one direction, rationally sifting through all these factors for every little decision is unrealistic so we usually don't. It's often easier to succumb to just succumb to the impulse.
This isn't breaking news or anything. Sad people eat more ice cream, stressed people take more naps.
But why are sad people sad? If the sad person wants to put themselves in a position where they no longer want to eat ice cream, how do they?
Sad people are sad as a consequence of prior decisions and influences, which themselves were the consequence of prior decisions and influences.
You're sad because you got stressed one day, happened to be outside of an ice cream shop, ate a ton of ice cream, skipped the gym for a few days, fell out of the habit, stopped waking up early, got insecure about your weight, got depressed, started sleeping more, got fatter, etc.
When considering a decision, it's less useful to measure the short run impact of it. "Sure I can skip the gym tonight, I'm tired and I've been doing great for weeks."
The short run impacts of decisions are much easier to both calculate and rationalize.
What you must consider when making a decision is not necessarily the immediate consequence, but rather the set of decisions you will be subsequently faced with.
It's a bad bet to assume that future you will be internally sound, rational, and clear-headed when making a future decision. It's better to assume that you'll be an impulsive monkey quick to jump into the worst option possible.
With each decision you make you move down a path. It's impossible to move backwards, and with each movement forwards you may lose alternate paths that were otherwise open (for example if you're 90 it's not possible for you to get into the NBA and have a successful career).
With each decision you move through a single path yourself and through a family of interconnected alternate paths you can take.
When considering a decision, you must consider the not the short run outcome of the decision, but rather the path you're taking. Out of all the paths you could go down, is this the one you want?
Is the short run outcome of this decision sound, but pushes you down a path that has serious negative consequences if the future you is irrational?
Let's say you're a successful musician. You've taken all the right steps to manifest that life. But now that you're there, you're presented with some dramatic options.
You're at a party. There are tons of dope artists there that you want to collaborate with. Doing so will propel your career even further. You're presented with a choice: do you have a sober chat with them about the music industry and organizing a studio session together, or, when one of them pulls out heroine, do you take it with them and bond––with the hopes of a chance to collaborate in the future?
One option might not have as high a success rate, but doesn't risk your life. The other has a good chance at helping you get what you want, but will probably fuck your entire life up.
Which path do you choose? Present you is probably like, "Well if they don't want to have a nice sober chat with me fuck them, I'm not going to just spontaneously take heroine." But future you is super drunk, has had the best 3 years of their lives, is surrounded by the best musicians in the world, and is craving for even more.
There's a chance future you'll fuck around and become a heroine addict. That alone shouldn't dictate your decisions, but it's important to consider.
I know, I know, that's an extreme example. But it's possible.
Each decision is a step through a tree of possible lives. It's important to consider the life you're walking through, and the consequential lives you could walk through if you make either the right or wrong decisions.
If you never consider the possibility of a drunken heroine high, when you're faced with that decision, there's a greater chance you'll fold.