Why do these psychology textbooks use 'differential'?

As English isn’t my first language, I don’t understand the difference between differential and ‘different’ as adjectives. Why do these books use ‘differential’? Why not just write ‘different’?

  1. Zoltan Dornyei. The Psychology of Second Language Acquisition - Oxford Applied Linguistics. Anyone know the page #?

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  1. Mario Bunge, Ruben Ardila. Philosophy of Psychology, p 228.

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  1. Critical Psychology: An Introduction edited by Dennis Fox, Isaac Prilleltensky. p. 238.

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edited by Dennis Fox, Isaac Prilleltensky. p. 238.

ilovephilosophy.com/viewtop … F#p2825438

Try the above - it’s possible there may be some kind of connection. Who knows… you may even find a suitable explanation for your query! :slight_smile:

There is no real practical difference between difference and differential. The both have the same Latin defivation and their use is almost interchangable.
There can be a valubale difference in usage but this is not often adhered to.
Let me think of an example.
There is a difference between cats and dogs. But you would not easily use “differential” as that would have to refer to the quantitative or qualitative difference, rather than the fact that they are different.
Being specific you might talk about their average weights; that would be chosing a specific differential.
The difference would be a number, the differential might be the range of differences.

My advice would be to not worry about the difference. Take ther words as interchangable and you will learn over time to get the context of the meanings.