memory's or memories?

[LittleEsmeWeatherwax]

DH can't agree on spelling

2 memories/y's are better than 1.

Help!

Memories

Memories because it is a plural. Memory's would either be abbreviation of memory is or something belonging to the memory.

I think you want the plural: "two memories are better than one".

You might want the singular possessive form for a sentence like: "the memory's sudden impact stopped me in my tracks".

The apostrophe indicates belonging. What does the memory own?

An apostrophe is never used for a plural. Never.

Thank you Pedants!
I've learnt something tonight.

Never use an apostrophe for a plural.