Picard stumps data by asking him how wrong actions lead to a greater good. But it happens all the time, ends justify the means logic. In our own history like dropping the heroshima bomb to save millions of lives or killing of innocent people during an anti-terrorism attack.PICARD: Data, it's not too late. If you remove the fibres, then Geordi might yet recover.
DATA: That would not be possible.
PICARD: Why? Because Lore tells you so?
DATA: It is for the greater good.
PICARD: Good? Data, isn't good and bad, right and wrong, a function of your ethical programme?
DATA: That is correct.
PICARD: What does that programme tell you about what you're doing to Geordi? About what you and Lore are doing to the Borg? It tells you that these things are wrong, doesn't it, Data? So how can actions that are wrong lead to a greater good?
DATA: You are attempting to confuse me.
PICARD: No, you're not confused, Data. You're sensing the truth. Your ethical programme is fighting the negative emotions that Lore is sending you.
Or in Star Trek history like:
TNG "The High Ground" - terrorism to fight oppression
DS9 "In the Pale Moonlight" - killing people to bring the Romulans into the war to save the alpha quadrant
TOS "The City On The Edge of Forever" - allowing someone to die to preserve the timeline
VOY "Tuvix" - killing one person to save two people
ENT "Anomoly" - torturing someone for information to help save Earth
DIS "Choose Your Pain" - killing lifeform / genetic experimentation used to save their captain
Lore justified the experiments already here:
Was Picard's question a valid reason for Data to question his motives? I'm wondering if the writers just forced Data to be confused to save time given that the episode was almost over.LORE: I thought it might look good on me. What do you think? Maybe we should work on your sense of humour, brother. Actually, I was thinking La Forge's implants might make him an ideal test subject for my experiment.
DATA: All the Borg you have experimented on so far have suffered extensive brain damage.
LORE: Using the humans to perfect the procedure will allow us to prevent any further Borg deaths.