Is there a difference in meaning between "I choose" and "I'll choose" when making a decision in the process of speaking?

Question

Would you tell me if there is a difference in meaning between I choose and I'll choose when making a decision in the process of speaking? For example:

Person A: We have two tablets of that brand. One with 3GB of RAM and one with 4GB of RAM.

Person B: I choose/I will choose the one with 4GB of RAM.

What English grammar books say is that the future simple can be used when someone makes an instantanous decision. But, I've also hear native speakers use the present simple in that sense, as in my example. Is there any difference between the two in the context? Are both natural? If so, do native speakers of English sense any difference between the two?

Answer 1

There's nothing wrong with using the future tense in OP's context - but it adds nothing, so most native speakers [will] stick with the the "default" position (prefer the simplest verb form that's grammatically and semantically valid for the context).

Obviously in this exact context the speaker is effectively making his choice as he speaks. There are some contexts where it's meaningful to say the choice really will be made later - for example, I'm not sure yet, but I think I will choose the 4Gb version. But other than that the choice is of no significance.

You might say I'm choosing a dress to wear to the party to refer to the "extended" activity (of "evaluating alternatives") that you're currently engaged in (with the implication I haven't yet made my final choice; the selection process is still ongoing). It would be a bit unusual to use the continuous in a "performative act" context (I'm choosing this dress, so can you tell me the price?).

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TL;DR: Use the simplest verb form by default, and only consider alternatives in specific contexts where you know you have some reason for using a more complicated form.

Answer 2

The normal tense for making a choice in the moment is will-future (I don't call it "future simple" because it's not simple either in structure or in function).

It's possible to use present simple for the function of announcing a decision that's already been made in the past. For instance, in player drafts in sports leagues, teams announce their choice with present simple, not will-future:

... the Detroit Red Wings select ... Moritz Seider.

source

But that's not the same function as a decision in the moment.

This becomes clear when we use a verb other than "choose" or "select". For instance, if we use "take" instead, only the will-future is grammatically correct in a store when you've made your decision:

A: Have you decided what you'd like to purchase?
B: Yes, I'll take this dress.

but not:

A: Have you decided what you'd like to purchase?
B: Yes, I take this dress.

So will-future is the correct choice in this context.