Explanation and reason why sometimes accusative and sometimes dative

[Nicodimo]

Hello.

As you may already know, two-case prepositions sometimes take the accusative and sometimes the dative. This has to do with what I am expressing. If a movement, a change, a displacement is expressed, then the accusative is used. But otherwise, when a fixed place is maintained, the dative is used. I think you understand what I mean.

I am trying to come up with a linguistic explanation for this phenomenon. Is there a linguistic reason for this that displacement is equivalent to accusative and not displacement is equivalent to dative? Perhaps a diachronic, historical explanation. I really don't understand why, when there is a displacement, a direct object is provided (ACCUSATIV). And when not, an indirect object is provided (DATIV).

In addition, it is very difficult for me to come up with a mnemonic rule that allows me to reason quickly enough, so that I can decline while I speak. (Currently I study a B1 course in German.)

Many many thanks, in advance, to anyone who can help me.

 

[Hutschi]

Hi, there is a rule of thumb, indeed. It mostly works, with some exceptions (as always).

The rule is: If the preposition indicates the goal/destination (directly or figurative) accusative is used. In English you would ask "wereto?".

If it is not a destination but a movement at a place it is mostly dative (where is it?).

Example

Ich gehe ins Haus. I am outside and the destination is the inside.
Ich gehe im Haus (hin und her). I am in the house, there is no destination.

Ich gehe auf die Straße. The street is the destination. E.g. I am at a sidewalk and go from there on to the street.
Ich gehe auf der Straße. I am walking along the street. or I am going on the street. (The street is not the destination but the place of movement.)
Ich stehe auf der Straße. No movement, no destination, just a place. Dative.

This is only a rule for two-case prepositions.

In some cases it is difficult to decide.

Ich schreibe auf die Tafel and Ich schreibe auf der Tafel are pragmatically the same. The difference is the point of view.

Note: In school they often say Movement causes accussative, no movement dative. This is true in many cases but with much more exceptions. (Ich gehe auf die Straße vs. Ich stehe auf der Straße.) Exception: Ich gehe auf der Straße.

 

[JClaudeK]

a direct object is provided (ACCUSATIV). And when not, an indirect object is provided (DATIV).

Es handelt sich hier nicht um "direkte oder indirekte Objekte", sondern um Ortsbestimmungen.
Der Dativ oder der Akkusativ haben sehr viele Funktionen:

Siehe Wikipédia:

• 1 Dativ als indirektes Objekt
• 2 Dativ bei Präpositionen
• 3 Typen
  • 3.1 dativus commodi bzw. incommodi
  • 3.2 dativus ethicus
  • 3.3 dativus possessivus
  • 3.4 dativus iudicantis
  • 3.5 dativus finalis
  • 3.6 inkongruenter Dativ

Akkusativ:

• 1.2 Grammatische Auslöser für den Akkusativ
  • 1.2.1 Regierter Akkusativ
  • 1.2.2 Der Gleichsetzungsakkusativ
  • 1.2.3 Der adverbiale Akkusativ
  • 1.2.4 Der absolute Akkusativ

See also:
How to Decide Whether A Dual Preposition Is Dative or Accusative?

it is very difficult for me to come up with a mnemonic rule

What about this one (link above):

Some find it easier to remember the accusative-versus-dative rule by thinking of the "accusative" letter A on its side, representing an arrow ( > ) for motion in a specific direction, and the dative letter D on its side to represent a blob at rest

 

[Schlabberlatz]

If a movement, a change, a displacement is expressed, then the accusative is used. But otherwise, when a fixed place is maintained, the dative is used.

Questions around Wechselpräposionen are probably the most often asked topic in this forum.

What I have leaned from all the question is that the explanation accusative=movement and dative=no movement is probably the most misleading way to explain Wechselpräpositionen.

Accusative expresses the target, aim or destination of an action and dative the location (spacial and temporal) and the conditions under which an action happens. Search this forum for the keyword "Wechelpräposition" or "Wechselpräpositionen" and you will find many discussions about particular cases.

Example:
1) Er läuft in die Halle.
2) Er läuft in der Halle.
Both are correct.

I am trying to come up with a linguistic explanation for this phenomenon. Is there a linguistic reason for this that displacement is equivalent to accusative and not displacement is equivalent to dative? Perhaps a diachronic, historical explanation.

(in germanischen Sprachen hat der Dativ den Lokativ und den Ablativ absorbiert)

Zeitangaben mit Wechselpräpositionen unterliegen schlicht und einfach derselben Logik wie Ortsangaben: Lokativ->Dativ, Destinativ->Akkusativ.

The main difference is between languages like Greek or German that have retained the case system and languages like English and Italian that have lost it. In the former, the distinction is still grammaticalised while they can but don't have to be made (e.g. in English you can use into instead of in to express a destinative meaning). When a meaning is grammaticalised, this means that you have to have an opinion on whether or not you mean it in a locative or destinative sense even if the information isn't really needed in a specific context and by opting for one form you have to exclude the other interpretation.

 

[Minnesota Guy]

In addition, it is very difficult for me to come up with a mnemonic rule that allows me to reason quickly enough, so that I can decline while I speak. (Currently I study a B1 course in German.)

There are so many possibilities that I doubt one mnemonic could cover them all. What has helped me is to think of clusters of concepts, or words, that work in many situations. For example:

1) For describing the physical world, the destination/location distinction works pretty well.

2) However, verbs describing arrival, disappearing, and appearing do not count as "destination" verbs: verschwinden, ankommen, landen, and the like, use dative, not accusative.

3) Many situations involving thoughts and emotions use accusative: Ich bin verliebt in sie, ich denke an sie, ein Gedicht über sie. (But there are many exceptions to this one. Still, it works for me.)

But the area is quite intricate--I wonder if C1 or even C2 students would get every single usage correct!