Here he raises something which sounds rather useful, but upon consideration seems to be difficult to apply:
Only those evils which are sure to come at a definite date have any right to disturb us; and how few there are which fulfill this description. For evils are of two kinds; either they are possible only, at most probable; or they are inevitable. Even in the case of evils which are sure to happen, the time at which they will happen is uncertain. A man who is always preparing for either class of evil will not have a moment of peace left him. So, if we are not to lose all comfort in life through the fear of evils, some of which are uncertain in themselves, and others, in the time at which they will occur, we should look upon the one kind as never likely to happen, and the other as not likely to happen very soon.
For instance, we may assume that our philosopher was an anxious fellow and thus found himself worrying about things which may never happen. Or perhaps he had such a friend: the advice to “calm down” makes sense. The mere act of being anxious does nothing to solve a problem; one has an unpleasant sensation currently, but the current sensation does nothing to change tomorrow.
However, preparing for contingencies is wise. By preparing today, perhaps I can avoid an event tomorrow.
Moreover, how can we really know the probabilities of future events? Sure some things are less likely, but unlikely things happen.
Moreover, what about things which I know will happen? Should I be worried about such things.
His advice is: If it’s going to happen, it will. You don’t know; you can’t prepare; so don’t worry. I think a further part of advice is tied to his conception of the world. If the world is effectively random (in the sense that I can’t really know what will happen, and what will happen follows no prescription other than the laws of physics), a constant anxiety is a “natural” result.
In response, Schopenhauer offers only, look you’re just making yourself feel bad. That is true. But is sort of like walking blindfolded, knowing that at some moment, someone is going to hit in the head with a baseball bat. Sure feeling bad right now won’t stop the bat, but it is really hard to walk into such an end.
It makes a certain amount of “sense”, but it seems terribly difficult to maintain equanimity. The trouble with his advice is that the emotion is a proper interpretation of the world. The problem is not the interpretation, it is inability to alter the bad outcome.
There is no basis to not be anxious other than it feels bad.
Compare that with
Matthew 6:25–34 (ESV)
25 “Therefore I tell you, do not be anxious about your life, what you will eat or what you will drink, nor about your body, what you will put on. Is not life more than food, and the body more than clothing? 26 Look at the birds of the air: they neither sow nor reap nor gather into barns, and yet your heavenly Father feeds them. Are you not of more value than they? 27 And which of you by being anxious can add a single hour to his span of life? 28 And why are you anxious about clothing? Consider the lilies of the field, how they grow: they neither toil nor spin, 29 yet I tell you, even Solomon in all his glory was not arrayed like one of these. 30 But if God so clothes the grass of the field, which today is alive and tomorrow is thrown into the oven, will he not much more clothe you, O you of little faith? 31 Therefore do not be anxious, saying, ‘What shall we eat?’ or ‘What shall we drink?’ or ‘What shall we wear?’ 32 For the Gentiles seek after all these things, and your heavenly Father knows that you need them all. 33 But seek first the kingdom of God and his righteousness, and all these things will be added to you.
34 “Therefore do not be anxious about tomorrow, for tomorrow will be anxious for itself. Sufficient for the day is its own trouble.
Here, the command to not feel anxious is similar to Schopenhauer, on the ground that current anxiety does no good. But the counsel is based upon an assertion of providence: God is taking care of what is happening. The trouble with anxiety is not that it is ineffective. The trouble with anxiety is that it is irrational: the world is not running at chance.
Thus, at the level of immediate psychological sensation, the advice is similar; but the ground of the advice is fundamentally different. Schopenhauer: the world is random, so why concern yourself with what will happen? Your current bad feelings are warranted, but won’t help.
Or, you’re in a car which is careening out of control down a hill. You’ll crash in a few minutes or a few seconds; don’t know which. Being afraid makes all sorts of sense; but it really won’t slow down the car. Your emotion is rational, but ineffective.
Jesus: the world is under the providential control of God, so why are you worried? Your current bad feelings are based upon a misunderstanding of the world.
You’re in a car which is being driven by an ultimately skilled driver. There’s no reason to be afraid. Your fear is based upon a misunderstanding; it makes no sense.